Bolt kits include the highest quality bolts and any other necessary hardware to attach a rotor, rotor mounting hat, hub, or live axle rotor clamp to a threaded or through hole mount. With a few exceptions, most bolts are drilled for lock wire. These Wilwood brake caliper bolt kits are designed to mount your caliper to the caliper mounting bracket. They are made of high-strength steel and are black oxide coated for a durable finish. The bolt kits include shims to make sure that the caliper spacing correctly fits the rotor width.