D, a swimming pool manufacturer, made and distributed a line of above-ground pools. Arthur Henry bought a D pool and assembled it in his backyard. The pool was a twenty-foot by twenty-four-foot model, with four-foot walls. An embossed vinyl liner fit within the outer structure and was filled with water to a depth of approximately three and one-half feet. At one point, the outer wall of the pool bore the logo of the manufacturer, and below it a decal that warned 'DO NOT DIVE' in letters roughly one-half inch high. P, then twenty-three years old, arrived uninvited at the Henry home and dove into the pool. A fact issue exists whether P dove from the platform by the pool or from the roof of the adjacent eight-foot high garage. As his outstretched hands hit the vinyl-lined pool bottom, they slid apart, and P struck his head on the bottom of the pool, thereby sustaining his injuries. P alleged that d was strictly liable for his injuries because it had manufactured and marketed a defectively designed pool. An expert in the characteristics of vinyl testified that wet vinyl was more than twice as slippery as rubber latex, which is used to line in-ground pools. The trial court, however, sustained an objection to the expert's opinion about alternative kinds of pool bottoms, specifically whether rubber latex was a feasible liner for above-ground pools. The expert admitted that he knew of no above-ground pool lined with a material other than vinyl, but P contends that vinyl should not be used in above-ground pools, even though no alternative material was available. A second expert testified that the slippery vinyl bottom and lack of adequate warnings rendered the pool unfit and unsafe for its foreseeable uses. D's expert testified that vinyl was the best material because it permitted the outstretched arms of the diver to glide when they hit the liner, thereby preventing the diver's head from striking the bottom of the pool. The trial court instructed the jury on the elements of strict liability, both with respect to design defects and the failure to warn adequately. The court limited the jury's consideration to the adequacy of the warning. That is, the court took from the jury the issue whether manufacturing a pool with a vinyl liner constituted either a design or manufacturing defect. The jury found that D had 'manufactured a product that was not reasonably fit, suitable and safe for its intended or reasonably foreseeable purposes or use,' that the defect existed when the product left D's control, and that the defect was a cause of P's injury. The jury found that P was a trespasser, rather than a social guest, at the time of the accident, thus exculpating the Henrys. The jury found that P was guilty of contributory negligence, and allocated fault for the injury as 15% attributable to D and 85% attributable to P. P was thus barred from recovery. The Appellate Division found that the trial court erred in removing from the jury the issue of design defect. That court reversed the judgment against D and remanded the matter for a new trial.