Clean rowdy trail sections and gut wrenching steeps with the confidence afforded by the powerful SRAM Guide R Disc Brake. Overhauled from previous SRAM offerings, the Guide R Disc Brake employs a new master cylinder for higher levels of braking precision and consistently powerful stopping performance. Its 4 piston, dual diameter caliper and steel backed organic brake pad provide brute stopping in all conditions. Another big change over previous SRAM brakes is the revised Timing Port Closure, with its sliding cup seal and port mechanism. This new system provides immediate actuation with the DirectLink lever, which also facilitates fantastic one finger modulation. Moreover, the DirectLink lever features tool free Reach Adjust for quickly personalizing your set up. Note that the Guide R Disc Brake comes in either frontleft or rearright variants, with included lever and caliper configuration. It's compatible with SRAM's Centerline Rotors sold separately and uses DOT 5. 1 fluid. Additionally, the Guide R is Matchmaker compatible, meaning you can run multiple controls off one lever clamp for a more streamlined set up.