Bird Life presents the Natural E Cuttlebones by Penn-Plax. Change things up for your pet with our solid 2-Pack of Natural E Cuttlebones! Along with providing additional vitamins and minerals, our Natural E Cuttlebones allow for a subtle and stimulating change in your pet’s daily life. Shop Penn-Plax for All Your Pet’s Needs: Penn-Plax is a manufacturer and distributor of top quality pet supplies, who specialize in creating excellent pet products for animals, both great and small.