The Rhino Skin is a durable polyurethane foam that features a tough outer coating to protect it from the elements. Rhino Skin balls are ideal for any age group, easy to clean and disinfect, and will even retain their shape after being kicked, squished, squeezed, or stepped on. Assorted colors set contains 6 balls. Neon colors set contains 6 balls. Metallic colors set contains 3 balls. Each ball is 6" in diameter.