Description Size Guide Health & Safety Care Review Warranty and Guarantee Help Made of natural caoutchouc rubber, which is gentle on dogs' teeth. Due to its grooved pattern, the surface is comfortable and secure to grip. The attachment of the string is very stable, and during heavy use, the string itself has great tensile strengh. The product is available in 3 sizes, so you can find the right one for whichever breed you have. The colour of the string may vary. Small: 50mm Diameter Medium: 60mm Diameter Large: 70mm Diameter