This is the silver disc brake caliper that is most often used on gas & electric scooters, go karts, dirt bikes, mini bikes, and pocket bikes with disc brakes. Both this brake caliper assembly and our premium quality brake assembly are compatible parts on most models from Dynacraft, Baja Motorsports, EVO, eZip, and Razor (including both the MX500 & MX650 electric dirt bikes). The bolt hole center to center distance is 2″ (51 mm). Silver finish Perfect for scooters & mini bikes For disc brakes Fits many models