These are heavy duty spring retainers, designed to hold down the front spring on its seat when used with our challenge suspension kit.
The spring retainers hook around the inner part of the coil spring allowing the spring to lift off the spring seat on the wheel side to take the pressure off twisting the spring on full drop out, see second picture.
Sold as a pair and come with all bolts, nuts and washers required to fit them, they are also galvanized to prolong there life.