Sporn® Durable Marrow™ Chew Bones are chewable nylon bones with "Peanut Butter Flavor Down the Middle!" Perfect for strong chewers, nylon shavings act like a toothbrush and help remove tartar from the dog's teeth. Unlike traditional rawhide bones, this bone will last! Marrow™ Chew Bones are available in 5 sizes to suit every size dog.