1.This product is a dog toothbrush that can't be bitten or broken. Outside is made of healthy and environmental nylon material, which is hard to bite inside is made of high toughness and soft TPR material. This toy is suitable for small, medium and large dogs to play without damage to dog's gums, even playing for a long time. 2.The design of three different strength serrated molar protrusions is fully surrounded in 360 degree,which can deeply cleandog's front teeth,cuspid teeth and molars,also remove all kinds of rice reside,dirt and dental calculus effectively to fully protect dog'sdental health.The cleaning function is far superior to similar products on the market,truly protecting dog's oral health. 3.Dog toothpaste or attractant can be applied inside the aisle when dog is playing , so as to attract the interest of dog , truly realizing the function that dogs brush teeth on own while playing. 4.Dog treat bars can be placed in the middle aisle of the toy,to attract dog's attention to play,so that this toy can be used as a clean dog's teeth while playing,to protect dog's oral health for a long time,but also burn up dog's extra energies,improve dog's intelligence and relive daily anxiety , preventing dogs from destroying furniture or clothes when the owner is not at home. 5.When dog plays this toy at the first time or large dogs play with this toy , we recommend to control the playing time within 15minutes,after which it can be increased to 20-30 minutes per day.