HERO Outer Armor toys are made using a special proprietary, multi-layered manufacturing process that brings together different materials to create a new standard in durable play. The process blends two layers of thermoplastic rubber (TPR) with a layer of durable mesh. When it comes to durability, three layers are better than one! The result is an extremely durable fetch, toss, and squeak toy with a unique look and feel that dogs and their owners love. They float and squeak as well!