Petitioner The Buckeye Boiler Company seeks a writ of mandate to compel the respondent superior court to quash the service of summons upon it in an action f< personal injuries brought by real party in interest Waym; P. Flynt. Involved is the scope of jurisdiction of Californ courts over foreign corporations claimed to be “doing bus ness in this state. ’ ’ (Code Civ. Proc., § 411, subd. 2.)

The record shows that on or about March 15, 1967, whi acting in the course of his employment at the General Blectr Company’s plant in Ontario, California, plaintiff was injure by the explosion of a.pressure tank containing an unidentifie liquid and being used in connection with a system for tb spraying of liquid under air pressure. The tank, it is allege* bore a metal nameplate with the legend: “The Buckey Boiler Company, Dayton, Ohio. Built 1960 — 150 lbs, max mum; ’ ’ and was, according to the record, being put to a us for which it was intended when manufactured. While recen ing treatment in a California hospital for his injuries resul! ing from the explosion, plaintiff it is claimed suffered a fal after which he was stricken with left hemiplegia, that is, tota paralysis of his entire left side.

Plaintiff sued Buckeye, alleging inter alia negligent manu facture of the pressure vessel, manufacturer’s strict liability and breach of warranty. By amended complaint, plaintif joined as defendants the doctor by whom and the hospital ir which he was treated for his injuries [hereinafter “medica defendants”], alleging that the fall he suffered resulted iron their negligence, and further alleging that he is in doubl whether his hemiplegic condition resulted from the explosion the negligence of the doctor and hospital, or both.

Service of process upon Buckeye was effected by personal delivery to the Secretary of State, pursuant to section 411, subdivision 2, of the Code of Civil Procedure. Buckeye appeared specially (Code Civ. Proc., §416.3) and moved to quash the service of summons on the ground that it was not doing business in the State of California and therefore could not properly be served with process pursuant to section 411, subdivision 2. The motion was denied.

The medical defendants consist of a California corporation and an individual who is a California resident, both of whom allegedly cannot be sued in any other state on plaintiff’s asserted causes of action. All witnesses of the accident reside in California.

Buckeye is a foreign corporation, organized and existing inder the laws of the State of Ohio, with its principal place if business and principal offices in Dayton, Ohio. It manufactures pressure vessels which have numerous and varied ises. Sales are solicited outside Ohio in interstate commerce >oth directly and through independent manufacturers ’ representatives who sell Buckeye’s products on a commission basis in Ohio, Kentucky, Michigan, Indiana, Pennsylvania, New lersey, New York, Connecticut, Maryland, Delaware, North Carolina, South Carolina, West Virginia, Virginia, Georgia, Florida, and Alabama. Buckeye does not advertise its products.

Buckeye has no agent, office, sales representative, exclusive agency or exclusive sales outlet, warehouse, stock of merchandise, property, or bank account in California. It does not sell on consignment to, and has no commission agreement with, any person or entity in California. However, for a period of five years prior to plaintiff’s injury, and continuing to the present, Buckeye has sold pressure tanks to Cochin Manufacturing Company, an Ohio corporation, which maintains a manufacturing plant in South San Francisco, California. Cochin orders some tanks directly from that plant; the purchases of other tanks are negotiated through its Ohio office. Buckeye ships the tanks (priced at $55 to $60 each) directly to the Cochin plant in South San Francisco. Annual gross sales to Cochin during the last two or three years have ranged from $25,000 to $35,000. Cochin manufactures hydraulic automobile lifts for service stations • it incorporates the tanks purchased from Buckeye into these lifts and then sells the lifts to purchasers throughout California and in other states. Cochin apparently does not resell Buckeye’s tanks for other uses.

Buckeye claims that other than sales to Cochin it has had “no contact with anyone in the State of California” and that it has not sold any of its products to the General Electric Company between January 1960 and the present. However, Buckeye admits that it has no records of its sales prior to 1962.

Buckeye ships to the Cochin plant in South San Francisco tanks identified in its invoices as “Hydraulic Oil Tanks” which are generally 14 inches in diameter and 75 inches in height. Apparently the exploding tank which allegedly injured plaintiff was approximately 10 inches in diameter and 16 inches in height. There is no evidence in the record befor us, other than the evidence of size and general type of use, t indicate what significant differences there may be between th tanks purchased by Cochin and the tank which alleged! injured plaintiff.

Plaintiff is unable to establish where his employer pui chased the exploding tank. The chief of the purchasinj department at General Electric’s Ontario, California, plan testified that the company has no record of purchasing th tank in question, or any other item, from Buckeye. He als testified that the department destroys records more than fivi years old. However, he stated that it was the department’ policy to purchase equipment, whenever possible, from sup pliers located within the State of California.

Section 411, subdivision 2, of the Code of Civil Proce dure authorizes service of process on foreign corporations “do ing business in this state. ’ ’ This section exerts the full powei of the state, consistent with the due process clause, to subject foreign corporations to the jurisdiction of California courts. (Fisher Governor Co. v. Superior Court, 53 Cal.2d 222, 224 [ 1 Cal.Rptr. 1 , 347 P.2d 1 ].) Thus, in a case such as the present one where a foreign corporation contends that service! of process upon it is not authorized by section 411, we must determine “whether jurisdiction may constitutionally be assumed.” (Id., at p. 225.)

A defendant not literally “present” in the forum state may not be required to defend itself in that state’s tribunals unless the “quality and nature of the defendant’s activity” in relation to the particular cause of action makes it fair to do so. (Hanson v. Denckla, 357 U.S. 235, 253 [ 2 L.Ed.2d 1283, 1297 , 78 S.Ct. 1228 ]; McGee v. International Life Ins. Co., 355 U.S. 220 [ 2 L.Ed.2d 223 , 78 S.Ct. 199 ]; Henry R. John & Son, Inc. v. Superior Court, 49 Cal.2d 855, 860 [ 323 P.2d 437 ].) Such a defendant’s activity must consist of “an act done or transaction consummated in the forum State” or “some [other] act by which the defendant purposefully avails itself of the privilege of conducting activities within the forum State, thus invoking the benefits and protections of its laws.” (Hanson v. Denckla, supra, at pp. 251, 253 [2 L.Ed.2d at pp. 1296, 1297].) Furthermore, unless the defendant’s forum-related activity reaches such extensive r wide-ranging proportions as to make the defendant suffi-iently “present” in the forum state to support jurisdiction ver it concerning causes of action which are unrelated to that etivity (Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 225 , and authorities cited therein), the particular ause of action must arise out of or be connected with the lefendant’s forum-related activity. (McGee v. International Life Ins. Co., supra, 355 U.S. 220, 223 [ 2 L.Ed.2d 223, 226 ]; I nternational Shoe Co. v. Washington, 326 U.S. 310, 319 [ 90 L.Ed. 95, 103 , 66 S.Ct. 154 , 161 A.L.R. 1057 ].)

Once it is established that the defendant has engaged in etivity of the requisite quality and nature in the forum state md that the cause of action is sufficiently connected with this ictivity, the propriety of an assumption of jurisdiction de-lends upon a balancing of the inconvenience to the defendant n having to defend itself in the forum state against both the nterest of the plaintiff in suing locally and the interrelated nterest of the state in assuming jurisdiction. (McGee v. International Life Ins. Co., supra, 355 U.S. 220, 223 [ 2 L.Ed.2d 223, 226 ]; Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 225-226 .) In other words, once the threshold of sufficient activity by the defendant has been oassed, the question of the propriety of subjecting the defend-mt to the jurisdiction of the forum involves both a consideration of fairness to the plaintiff (see Phillips v. Anchor Hocking Glass Corp. (1966) 100 Ariz. 251 [ 413 P.2d 732 , 19 AL.R.3d 1, 7]) and a determination of whether, from a standpoint of the logical and orderly distribution of interstate litigation, the forum state is what Professor Ehrenzweig has termed a “forum «mveniens.” (See Ehrenzweig, The Transient Rule of Personal Jurisdiction: The “Power” Myth and Forum Conveniens (1956) 65 Yale L.J. 289 , 312; see generally, von Mehren and Trautman, Jurisdiction to Adjudicate: A Suggested Analysis (1966) 79 Harv.L.Rev. 1121.)

The forum state, of course, has an interest in opening its courts to residents seeking redress (Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 225 ), particularly when its courts arejthe only ones accessible to them _as a practical matter. It also Has an” interest, from the standpoint of the orderly administration of the laws, in assuming jurisdiction in cases where most of the evidence, testimonial and otherwise, is within its borders and where prevailing choice of law principles dictate the application of local law to the major issues involved. (Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 225 ; Gray v. American Radiator t Standard Sanitary Corp., 22 Ill.2d 432 [ 176 N.E.2d 76] 766].)

The plaintiff, of course, has an interest in presenting hi claim in court and in obtaining relief if it is warranted. A already indicated, suit in a local court may be his only practi cal opportunity to accomplish this objective. Both the plaintii and the state may have an interest in avoiding multiple am possibly conflicting adjudications. (Compare Empire Stee Corp. v. Superior Court, 56 Cal.2d 823, 833 [ 17 Cal.Rptr. 150 366 P.2d 502 ], with Henry R. Jahn & Son, Inc. v. Superio Court, supra, 49 Cal.2d 855, 862 .) On the other hand, a non resident defendant which derives economic benefit from aetiv ity in the forum state and thus does more than a purely loca business ordinarily has very little basis for complaining o: inconvenience when required to defend itself in that state (McGee v. International Life Ins. Co., supra, 355 U.S. 220 223-224 [ 2 L.Ed.2d 223, 226 ]; Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 225-226 ; see von Mehren and Trautman, supra, 79 Harv.L.Rev. 1121, 1167-1168, 1172-1173.)

The present case calls for an application of these principles to the field of products liability (see generally, Annotation Products Liability: In Personam Jurisdiction Over Nonresident Manufacturer or Seller Under “Long-Arm” Statutes 19 A.L.R.3d 13 ; Comment, In Personam Jurisdiction Over Nonresident Manufacturers in Product Liability Actions (1965) 63 Mich.L.Rev. 1028), a field in which the United States Supreme Court has not yet provided explicit guidance.

Courts and commentators have expressed differing views on whether the statement in Hanson v. Denckla, supra, 357 U.S. 235, 253 [ 2 L.Ed.2d 1283, 1297 ], that jurisdiction over an absent nonresident defendant can only be predicated upon activity which the defendant “purposefully” conducts within the forum state, applies in all cases, including products liability actions against nonresident manufacturers, or is uited to cases factually similar to Hanson (Compare eflar, Conflict of Laws (1959) 34 N.Y.U.L.Rev. 20, 33; hode, In Personam Jurisdiction; Article 2031B, the Texas Long Arm” Jurisdiction Statute; and the Appearance to challenge Jurisdiction in Texas and Elsewhere (1964) 42 ex.L.Rev. 279, 301-310; with Phillips v. Anchor Hocking lass Corp., supra, 19 A.L.R.3d 1, 7-8, 10 ; Comment, Tortious ct as a Basis for Jurisdiction in Products Liability Cases 1965) 33 Fordham L.Rev. 671, 685-686.) This court has iparently taken the former and sounder position, that the anson formulation of the “minimum contacts” test (International Shoe Co. v. Washington, supra, 326 U.S. 310, 316 [ 90 L.Ed. 95, 102 ]) is generally applicable. (Fisher Governor Co. Superior Court, supra, 53 Cal.2d 222, 225-226 ; see also Jaco-Porter Corp. v. Superior Court, 211 Cal.App.2d 559, 64-565 [ 27 Cal.Rptr. 371 ].) Thus, we must consider what the anson rule means in the products liability context.

In Fisher Governor, supra, we intimated that a nonresident anufacturer “purposefully” conducts activities within the >rum state, within the meaning of Hanson , if it “knowingly g'eet[s] itself into a transaction . . . having substantial Cal-ornia contacts related to the causes of action.” (53 Cal.2d t p. 226.) In Empire Steel Corp. v. Superior Court, supra, 56 Cal.2d 823, 834 , we recognized that an enterprise obtain[s] the benefits and protection of our laws” if, “as a Latter of commercial actuality, [it] has engaged in economic itivity within this state. ...” (Italics added.) According ) Hanson , the requirement that the defendant engage in urposeful activity within the forum state is designed to emonstrate that the defendant has invoked such benefits and protection and is therefore amenable to jurisdiction in at lea I some cases. ( 357 U.S. 235, 253 [ 2 L.Ed.2d 1283, 1297 ].) Thu we have equated engaging in economic activity within th state “as a matter of commercial actuality” with Hanson requirement of purposeful activity within the state. (C McGee v. International Life Ins. Co., supra, 355 U.S. 220 , 222 223 [ 2 L.Ed.2d 223, 225-226 ].)

A manufacturer engages in economic activity within a sta1 as a matter of “commercial actuality” whenever the pu: chase or use of its product within the state generates gros income for the manufacturer and is not so fortuitous c unforeseeable as to negative the existence of an intent on th manufacturer’s part to bring about this result. (See, e.g Gray v. American Radiator & Standard Sanitary Corp., supra [ 176 N.E.2d 761, 766 ]; Metal-Matic, Inc. v. District Court, 8 Nev. 263 [ 415 P.2d 617 ]; DiMeo v. Minster Machine Co., 22 F.Supp. 569 [mere presence of product in state not enough t sustain jurisdiction]; Comment, supra, 63 Mich.L.Rev. 1021 1033-1034; but see Gill v. Surgitool Inc., 256 Cal.App.2d 583, 588 [ 64 Cal.Rptr. 207 ].)

A manufacturer’s economic relationship with a state doe not necessarily differ in substance, nor should its amenabilit; to jurisdiction necessarily differ, depending upon whether i deals directly or indirectly with residents of the state. “Wit] the increasing specialization of commercial activity and th growing interdependence of business enterprises it is seldon that a manufacturer deals directly with consumers in othe States. The fact that the benefit he derives from [their] law is an indirect one, however, does not make [those laws] any th' less essential to the conduct of his business; and it is no unreasonable, where a cause of action arises from allegec defects in his product, to say that the use of such products ii the ordinary course of commerce is sufficient contact witl [such states] to justify a requirement that he defend [there].’ (Gray v. American Radiator & Standard Sanitary Corp. supra [ 176 N.E.2d 761, 766 ].)

A manufacturer whose products pass through the hands oi one or more middlemen before reaching their ultimate users cannot disclaim responsibility for the total distribution pattern of the products. If the manufacturer sells its products in circumstances such that it knows or should reasonably anticipate that they will ultimately be resold_in_ a ^particular, state, it should be held to have purposefully availed itself of the market for its products in that state See, e.g., Keckler v. Brookwood Country Club, 248 F.Supp. 15, 647-649 ; Bibie v. T. D. Publishing Corp. (N.D. Cal. 66) 252 F.Supp. 185 .) In Regie Nationals Des Usines Renalt v. Superior Court, 208 Cal.App.2d 702, 703 [ 25 Cal.Rptr. 10 ], the court refused to exempt the defendant, a French corporation, from jurisdiction in a suit apparently for per-mal injuries although the defendant did not sell its cars irectly in California but rather “ inaugurate [d] a flow of its roduets to . . . California” through a “Chain of sales” volving a wholly owned American subsidiary and independ-ltly owned distributorships and dealerships. The court held Lat the indirect manner in which the defendant dealt with alifornia consumers “ effect [s] little, if any, alteration in the irisdictional situation.” (Cf. Empire Steel Corp. v. Superior Court, supra, 56 Cal.2d 823, 829-831 .)

The same focus on actual economic benefit should be made i cases where the middlemen between the defendant manu-icturer and the consumer include intermediate manufac-irers who incorporate the original manufacturer’s products ito their own as components thereof. (See Gray v. American adiator & Standard Sanitary Corp., supra [ 176 N.E.2d 761, 66 ] [defendant manufactured safety valves in Ohio, sold íem to a Pennsylvania manufacturer of water heaters which íeorporated the valves into its heaters and sold the heaters in linois and other states]; see also Stephenson v. Duiron Co. 1965, Alaska) 401 P.2d 423 , cert. denied 382 U.S. 956 [ 15 L.Ed.2d 360 , 86 S.Ct. 431 ]; Metal-Matic, Inc. v. District Court, supra, 82 Nev. 263 ; Golden Gate Hop Ranch, Inc. v. Telsicol Chemical Corp., 66 Wn.2d 469 [ 403 P.2d 351 ], cert. denied 382 U.S. 1025 [ 15 L.Ed.2d 539 , 86 S.Ct. 644 ].)

A number of recent decisions of the California Courts of appeal employ a mechanical “checklist” approach to deter-iine the existence or nonexistence of purposeful activity dthin the state. (See Gill v. Surgitool Inc., supra, 256 Cal.App.2d 583 ; DaSilveira v. Westphalia Separator Co., 248 Cal.App.2d 789 [ 57 Cal.Rptr. 62 ]; Twinco Sales, Inc. v. Superior Court, 230 Cal.App.2d 321 [ 40 Cal.Rptr. 833 ]; Yeck Mfg. Corp. v. Superior Court, 202 Cal.App.2d 645 [ 21 Cal.Rptr. 51 ] [does defendant have office, property, agent, mployees, jobber, distributor, manufacturer’s agent or other epresentative; is there solicitation or advertising' or was the ale made, in California].) This approach fails to focus on conomie reality rather than the outward form of business ransactions and is disapproved.

When a plaintiff is allegedly injured in the forun state by a defect in a nonresident manufacturer’s produd the question whether that product’s use or purchase was ai isolated instance or part of a continuous course of business ii the state is relevant but not necessarily decisive in determin ing the existence or nonexistence of the requisite jurisdictional activity. (Empire Steel Corp. v. Superior Court, supra 56 Cal.2d 823, 832 ; accord, Gray v. American Radiator & Standard Sanitary Corp., supra [ 176 N.E.2d 761, 764 ].) Onh if isolated use or purchase conclusively establishes lack o: foreseeability that the product will enter the state is the isola tion necessarily fatal to jurisdiction over the manufacturer in that event there is a manifest lack of purposeful activity oi the part of the manufacturer.

In the present case, it is clear that defendant derive substantial economic benefit from the sale and use of its products in California; it currently derives about $30,000 annually in gross sales revenues from its direct sales of certan pressure tanks to the Cochin Manufacturing Company plant in South San Francisco. On the basis of these sales alone, defendant is purposefully engaging in economic activity within California as a matter of “commercial actuality.’’

The trial court was warranted in concluding that defendant’s total economic activity in California consists of its direct sales to Cochin and some indeterminate amount of additional sales activity, direct or indirect; and that at some time during or subsequent to 1960 (the date of manufacture of the tank that allegedly injured the plaintiff) and prior to 1962 (the year prior to which defendant has no sales records) defendant sold the pressure tank that allegedly injured plaintiff either directly to the General Electric plant in Ontario, California, or through one or more intermediate parties. This tank may be the only Buckeye pressure tank ever sold in, or for use in, California other than the tanks sold to Cochin. Or it may be only one of a substantial number of pressure tanks purchased in, or for use in, California through the channels of interstate commerce in which defendant distributes many of its products. It is very possible that a number of the firms to which defendant sells its pressure tanks in the eastern half of the United States resell some of these tanks, either alone or as components of their own products, to customers in California. This distinct possibility is not negated by Buckeye’s somewhat rvasive statement in its response to plaintiff’s interrogatories hat other than its sales to Cochin it has had ‘ ‘ no contact with myone in the State of California. ’ ’

But whether the pressure tank that injured plaintiff is one >f a number of tanks sent into California by Buckeye through i “chain of sales’’ (Regie Nationale Des Usines Renault v. Superior Court, supra, 208 Cal.App.2d 702, 703 ) or is the lubject of an isolated California transaction apart from Buckeye’s sales to Cochin, plaintiff’s cause of action appears ;o arise from Buckeye’s economic activity in California, the ntality of its sales of pressure tanks to California customers or to other customers for foreseeable resale or use in California.

Buckeye did not allege before the trial court that the tank which allegedly injured plaintiff arrived in California in a nanner so fortuitous and unforeseeable as to demonstrate that its placement here was not purposeful. Nor did Buckeye there allege that the burden of defending the present action in California would be substantially different in its nature and extent than the burden of defending actions which might arise from sales of pressure tanks to Cochin. If Buckeye can demonstrate both of these propositions, an assumption of jurisdiction might well be inappropriate since it might then be said that plaintiff’s cause of action neither .arose from nor was connected, with any purposeful activity by Buckeye within the State of California. Since Buckeye’s position in the trial court was based in significant measure upon Court of Appeal decisions that have been disapproved for applying the purposeful activity test in too mechanical a fashion it should be afforded the opportunity of making the sort of evidentiary showing suggested above before the trial court, a showing which appeared unnecessary under those decisions.

The interests of both the plaintiff and the State of California appear to substantially outweigh any inconvenience of which defendant may complain in being required to defend the present action in California. The state has a substantial interest in affording the plaintiff, a California res: dent, a forum in which he may seek whatever redress i| warranted, especially where, as here, it is quite likely that th plaintiff cannot, for financial as well as possible physical reasons, pursue his claim in the distant state where the defen ant has its principal place of business. The plaintiff, in the present case, also has a peculiar interest in litigating locally The distinct preponderance of relevant evidence is located within California. Not only are all witnesses and records concerning explosion of the tank and the extent of plaintiff's injuries here, but a major piece of evidence concerning the question of defective manufacture—the tank itself—is also here. Choice of law principles followed in California and Ohio both appear to dictate the application of California law to the major substantive issues likely to be involved. (Compan Reich v. Purcell, 67 Cal.2d 551 [ 63 Cal.Rptr. 31 , 432 P.2d 727 ], with Gallegos v. Union-Tribune Publishing Co., 195 Cal.App.2d 791, 797 [ 16 Cal.Rptr. 185 ]; Gordon v. Reynolds, 187 Cal.App.2d 472, 477 [ 10 Cal.Rptr. 73 ]; see Collins v. McClure, 143 Ohio St. 569 [ 56 N.E.2d 171, 172 ].) Finally there may be a multiplicity of suits with possibly conflicting results if plaintiff is forced to sue defendant Buckeye in Ohic and the medical defendants in California. It will be recalled that plaintiff alleged in his amended complaint that he is ir doubt whether his present incapacitating hemiplegic condition was caused by the explosion or by the negligence of the medi cal defendants or both. He fears that if he is required to sue defendant Buckeye in Ohio and the medical defendants in California, the defendant(s) in each case may be able to avoid liability for this condition by pointing the finger at the absent defendant (s).

The plaintiff has made a sufficient prima facie showing that is injury arose from or is connected with purposeful activity i California — direct and indirect sales of pressure tanks — which produces economic benefit for Buckeye as a matter of commercial actuality. ’ ’ A balancing of inconvenience to the efendant against the interests of the state and the plaintiff in having the present litigation in California strongly favors ae local jurisdiction.

The alternative writ of mandamus is discharged and the pplication for a peremptory writ is denied.

Buckeye’s motion was originally granted without prejudice to a further application for substituted service by plaintiff supported by a showing of further jurisdictional facts. Substituted service was effected a second time and a second motion to quash service, opposed by affidavits setting forth the jurisdictionally relevant facts enumerated in this opinion, was denied. In a brief filed with this court Buckeye for the first time claims that the tanks purchased by Cochin bear "no relation" to the tank that injured plaintiff. So far, decisions of the United States Supreme Court delineating the due process limitations on in personam jurisdiction over corporations have dealt with liability for payments to a state compensation fund (International Shoe Co. v. Washington, supra, 326 U.S. 310), liability to a stockholder for dividends and for failure to issue stock certificates Perkins v. Benguet Min. Co., 342 U.S. 437 [ 96 L.Ed. 485 , 72 S.Ct. 413 ]), liability to the beneficiary under an insurance contract (McGee v. International Life Ins. Co., supra, 355 U.S. 220 ), and liability of a trustee to residuary beneficiaries of a will (Hanson v. Denckla, supra, 357 U.S. 235 ). In Hanson , a Pennsylvania domiciliary executed an inter vivos trust aming a Delaware trust company as trustee. She subsequently moved ) Florida where she executed a will and exercised her power of appoint-lent in the trust. After her death in Florida, beneficiaries under the ill brought suit in Florida to have the trust declared invalid. The five-idge majority opinion held that Florida had no jurisdiction over the 'elaware trustee, whose contacts with Florida primarily consisted of re-litting trust income to the settlor in Florida and making changes in the istrument at the request of the settlor while she was in Florida. The court states in Hanson : “The unilateral activity of those who [aim some relationship with a non-resident defendant cannot satisfy the squirement of contact with the forum State. The application of that ale will vary with the quality and nature of the defendant’s activity, ut it is essential in each case that there be some act by which the de-endant purposefully avails itself of the privilege of conducting activities dthin the forum State . . . .” ( 357 U.S. 235, 253 [ 2 L.Ed.2d 1283, 1297 ], italics added.) Defendant claims that it has not sold any of its products to General Electric between January 1960 and the present. However, defendant admits that it has no records of its pre-1962 sales. The record shows only that this tank may be the only Buckeye tank in California other than tanks sold to Cochin and that it may not have been sold directly to General Electric Company (see fn. 6, sitpra). Buckeye has argued before this court for the first time that the pressure tank which allegedly injured plaintiff is significantly different from the tanks it sells to Cochin. No particulars have been specified. The plaintiff has the burden of showing that a defendant is doing business in California for purposes of section 411 of the Code of Civil Procedure. (Agalite-Bronson Co. v. K. G. Limited, 270 Cal.App.2d 308, 310 [ 75 Cal.Rptr. 527 ].) Consistent with this rule, it would seem that where, as in the present case, the plaintiff establishes that the defendant is a manufacturer which frequently does not deal directly with the ultimate purchasers or users of its products; that its products are put to “numerous and varied uses” which are not readily apparent' to the average person; that a substantial amount of its business is conducted through the channels of interstate commerce; and that the defendant docs engage in some substantial economic activity within the state, it is reasonable to require the defendant to carry the burden of making the sort of showing outlined above in order to avoid jurisdiction over a cause of action such as that involved in the present ease. (Cf. Keckler v. Brookwood Country Club, supra, 248 F.Supp. 645, 647-649 ; Gray v. American Radiator & Standard Sanitary Corp., supra [ 176 N.E.2d 761, 764-766 ].) In Fisher Governor Co. v. Superior Court, supra, 53 Cal.2d 222, 223, this court noted that although the plaintiff alleged that jurisdiction oyer the nonresident corporation was supported by the desirability of avoiding multiplicity of litigation, there was no evidence in the record before he court to support the contention that the foreign corporation and the ther defendants, "various other corporations,” could not be sued in ,ny one forum outside of California. The court concluded no danger of nultiple litigation had befen shown. (Id., at p. 226.) This case is dif-erent. The other defendants here are a California doctor and the San Antonio (California) Community Hospital, a California corporation. ?here appears to be no reasonable possibility that any of these Cali-brada defendants could be sued in Ohio.