California first adopted the doctrine of strict products liability in Greenman v. Yuba Power Products, Inc. (1963) 59 Cal. 2d 57, 27 Cal. Rptr. 697, 377 P.2d 897, which stated at pages 62 and 63: "A manufacturer is strictly liable in tort when an article he places on the market, knowing that it is to be used without inspection for defects, proves to have a defect that causes injury to a human being. . . .The purpose of such liability is to insure that the costs of injuries resulting from defective products are borne by the manufacturers that put such products on the market rather than by the injured persons who are powerless to protect themselves." The doctrine of strict products liability applies to all persons in the chain of distribution of a defective product, including manufacturers, wholesalers, and retailers. (Soule v. General Motors Corp. (1994) 8 Cal. 4th 548, 560, 882 P.2d 298; Bay Summit Community Assn. v. Shell Oil Co. (1996) 51 Cal. App. 4th 762, 773.) In Vandermark v. Ford Motor Co. (1964) 61 Cal. 2d 256, at pages 262-263, 37 Cal. Rptr. 896, 391 P.2d 168, the court applied the doctrine of strict products liability to a retailer, stating: "Strict liability on the manufacturer and retailer alike affords maximum protection to the injured plaintiff and works no injustice to the defendants, for they can adjust the costs of such protection between them in the course of their continuing business relationship." Strict products liability may also apply to persons who are not directly in the vertical chain of distribution of a defective product, but who "play an integral role in the 'producing and marketing enterprise' of a defective product and profit from placing the product into the stream of commerce. " (Bay Summit Community Assn., supra, at p. 773.) "Unlike negligence, in which the focus is on the conduct of the tortfeasor, strict liability focuses on the product itself and holds the manufacturer, et al., liable if the product is defective. " (Edwards v. A.L. Lease & Co. (1996) 46 Cal. App. 4th 1029, 1034.) Kriegler v. Eichler Homes, Inc. (1969) 269 Cal. App. 2d 224, 227-229, 74 Cal. Rptr. 749, extended the doctrine of strict products liability to developers of mass-produced homes. Kriegler reasoned: "There are no meaningful distinctions between Eichler's mass production and sale of homes and the mass production and sale of automobiles and . . . the pertinent overriding policy considerations are the same." (Id. at p. 227; Del Mar Beach Club Owners Assn. v. Imperial Contracting Co. (1981) 123 Cal. App. 3d 898, 911-913, 176 Cal. Rptr. 886.) Strict products liability applies to both product design and manufacturing defects. (Ferrari v. Grand Canyon Dories (1995) 32 Cal. App. 4th 248, 257; Barker v. Lull Engineering Co. (1978) 20 Cal. 3d 413, 426, 143 Cal. Rptr. 225, 573 P.2d 443; Rest.3d Torts, Products Liability, 2.) Although the doctrine applies to defective products, it does not apply to defective services. (Hyland Therapeutics v. Superior Court (1985) 175 Cal. App. 3d 509, 513, 220 Cal. Rptr. 590; Endicott v. Nissan Motor Corp. (1977) 73 Cal. App. 3d 917, 930, 141 Cal. Rptr. 95; Rest.3d, supra, 19.) "Courts have not extended the doctrine of strict liability to transactions whose primary objective is obtaining services. Courts have also declined to apply strict liability where the transaction's service aspect predominates and any product sale is merely incidental to the provision of the service. " (Pierson v. Sharp Memorial Hospital, Inc. (1989) 216 Cal. App. 3d 340, 344, 264 Cal. Rptr. 673.) In Pierson, we stated: "A product is a physical article which results from a manufacturing process and is ultimately delivered to a consumer." (Id. at p. 345, italics added.) The Restatement Third of Torts, Products Liability, section 19, subdivision (a) defines the term product for purposes of strict products liability: "A product is tangible personal property distributed commercially for use or consumption. Other items, such as real property and electricity, are products when the context of their distribution and use is sufficiently analogous to the distribution and use of tangible personal property that it is appropriate to apply the rules stated in this Restatement."