The Box Disc Brake Adapter is designed to help improve braking control on frames where disc brakes were not standard. It goes over your hub’s axle and mates with the frame’s dropout, allowing mounting of a standard post mount disc brake caliper. Post mount caliper compatibility Only use a 140mm disc brake rotor Compatible with specific sliding plate dropouts with inserts (found on many Thrill, Haro, DK and Stay Strong aluminum frames) Includes two adapter rings that allow for compatibility with 3 brands of 10mm hubs only - Box Three Pro Disc (needs no adapter ring), Stealth 10mm Disc (requires S-spec adapter ring), and Onyx 10mm Disc (requires O-spec adapter ring) Will not fit hubs with 15/20 or step down axles 150lb rider weight limit
