Cosmic Crunch toys are made of 100% pulverized sea shells that provide caluium as they chew. They help to keep beaks and nails manicured as they play. Most toys hae glow in the dark beads - with an afterglow of 20 minutes. The toys last a long time - the material is so hard that they acually "shave away" at the material instead of chew it. This toy is designed medium to large birds.