At last...the ring to top them all. This Fisher-Price Rock-a-Stack toy, made from plant-based materials, offers classic stacking fun for babies. It features a wibbly-wobby rocker base and 5 colorful rings for little hands to grasp and stack. Stacking helps baby develop hand-eye coordination and introduces them to the concept of relative size as they learn to sort and stack from biggest to smallest! (Toy is made from a minimum of 90% ethanol extracted from sugar cane.)