The TireBiter Paw Tracks Extra Strength has been tested by an independent lab to be a safe non-toxic toy. TireBiter is the perfect dental chew device for your dog"s teeth. The combination of soft natural rubber and nylon fibers removes plaque and tartar build up. Great pets of all ages to enjoy! These can also be used as a training tool. The Toughest TireBiter Ever! Roll, Toss, Floss Heavy Duty 2 Ply Flossing Nylon Made with Natural Rubber - Extremely Durable Cleans Teeth and Gums Non Toxic / Tested Safe TireBiter Paw Tracks, Not Just a Toy, But A Training Tool: View PDF HERE