MATERIAL: The wheel is made of high quality PP.antifriction, aging resistance, high temperature resistance
INCLUDE: 2 pcs wheels+2 pcs brackets+2 pcs shoulder bolts+2 pcs lock nuts+6 pcs screws+6 pcs nuts.Easy to install.When the lock nut is tightened,the effect produced is exactly the same as that produced by a hammer driving in a wedge