For use on 1-3/4″ x 1-1/4″ tapered spindles. 6 stud with 6 on 5.5 bolt pattern. 12″ Vented Rotor Disc Brake Assembly. A vented rotor disc brake assembly with integral hub. Vented rotors and aluminum caliper assemblies allow heat to dissipate quickly to maintain optimum braking performance and efficiency. Ceramic brake pads with stainless steel backing plates eliminate the dust commonly associates with disc brakes. Vented rotor and Vortex hub have GalvX finish providing enhanced corrosion protection. Triple lip seal and Lucas Red N Tacky grease are used in each rotor/hub assembly. Caliper mounting bracket and hardware included