Product material：Flame retardant thermoplastic polyurethane raw material Product specification：537mm 179 teeth 519mm 173 teeth 480mm 160 teeth 573mm 191 teeth Product features：Simple structure, small size and easy replacement Precautions：Before replacing the belt, remove the residue on the gear Installation method：First place the belt on the pinion, and then place one side of the belt on the side of the big gear to make it rotate slowly