A 9-year-old boy and his friends were playing catch with a toy time bomb, a hard-surfaced plastic ball with a timing device protruding from the top of the ball. According to the directions accompanying this toy, each player's object is to toss the ball to another player before the ticking of the timer terminates with a loud bang. A friend excitedly threw the ball in the boy's direction. It bounced on the tile floor and struck him in the mouth, lacerating his lips and gums and fracturing two of his front teeth. Plaintiff's claim was based on expert testimony that the defendant's selection of a hard plastic surface for such a toy, knowing it would be thrown quickly and violently, was unsafe and improper.