Product advantages: 1, do not lightly brake locking, saving tire wear; 2, the no-load braking is very soft, easy to cause the hub of early wear and early rupture; to avoid skidding flick 3, rain and snow road when braking; 4, to the maximum extent to extend the service life of the brake system; 5, after repeated loading experiment of heavy can shorten the braking distance of more than 40%.