Shimano 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 Post Mount fork to use a 203mm disc brake rotor. Use only Shimano brake components for the best braking performance. Please note: thisadaptor is designed for the 160mmnativepost mount standard. Some newer forks are 180mm native and require a different adaptor for mounting. Please check your fork before ordering. Lightweight, Stiff Aluminum Construction For Post Mount forks with 160mm Post Mountto Post-Mount Calipers for use with203mm Rotor Includes mounting bolts and hardware Brake Caliper Mount: 74mm Post For Rotor Diameter: Front 203 mm Frame/Fork Mount: 74mm, 160mm Post Mount Caliper Type: 74mm Post Mount Rotor Size: 203 mm | Shimano | F203P/p Disc Brake Adapter 203Mm Rotor, 74Mm Caliper, 74Mm Fork