Bat, stack, shake, soothe, and discover with the Baby Einstein Stack & Wobble Zen Teether Toy. This colorful wobble toy helps encourage babys cause & effect learning. Brightly colored, BPA-free rings are textured to soothe sore gums and help build babys early sensory skills. Featuring Zen the Zebra from Baby Einstein shows and books, smaller infants will love to bat the stacker to make Zen wobble, promoting cause & effect learning and engagement. Use the 4 removable disks to teach older babies basic colors, counting, and stacking. Wipe clean with a damp cloth.