20 LARGE XXL FUN SCIENCE TOY: Giant Magic Grow Water Marbles Beads: Kits and Sets Expand Many x Volume Water Gel Balls 50 Eco-FRIENDLY NON TOXIC. Reusable up to 2 years THESE BALLS ARE REALLY COOL wet and wacky, soft and squishy, fun and funky, bouncy and beautiful. They start off hard and tiny. ABSORBENT ACRYLIC WATER BALLS are an amazing polymer that absorbs up to 200 times its size. MULTIPURPOSE: Toy-games Hours of educational fun for kids. Deco Centerpiece, Gift; ALSO FOR: autism sensory toys special needs processing integration sensorial fun science