3 sizes of dog toothbrushes: Suitable for all Small Medium Large Dogs. Choose the right size based on the size of the dog. Made of high quality rubber, nontoxic ,durable, 360-degree bristle configuration, bite resistance and easy to clean The Dog Toothbrush is a must-have for dog owners who want to keep their pet's teeth healthy and clean Automatically clean dog teeth: There is a toothpaste injection port at the top. During use, the toothpaste is automatically dispensed into the brushing groove by biting and squeezing to clean the dog's teeth. Usage: 1.Allow your dog to chew on the Brushing Stick for Dogs for about 10 minutes at a time. 2.This is enough time to clean his teeth, but not so long that he ’ll get bored of it. 3.When his or her 10 minutes are up, you should take the stick and put it up until next time.