Shimano XTR F203P/P Disc Brake Adaptor Shimano Disc Brake Adaptors are the finest disc brake adaptors available for Shimano disc brakes. Utilizing an extremely stiff aluminum construction, you will achieve your proper brake alignment and optimum function. This adaptor is for mounting a standard Post Mount caliper to a native 180mm Post Mount fork to use a 203 mm disc brake rotor. Use all Shimano brake components for the best braking performance. Lightweight, Stiff Aluminum Construction For Post Mount, 180mm-nativeforks to Post-Mount Calipers and 203mm Rotor Includes Mounting Bolts, washers and bolt securing wire Brake Caliper Mount: 74mm Post For Rotor Diameter: Front 203 mm Frame/Fork Mount: 74mm Post Mount, 180mm native Caliper Type: 74mm Post Mount | Shimano | Xtr F203P/p Disc Brake Adaptor 203 Rotor, Shimano | # Ismma90F203Ppm