TRP HY/RD disc brake calipers have the power and modulation of hydraulic disc brakes. True 'plug-and-play' compatibility with existing cable actuated systems. - Self-contained hydraulic caliper incorporates master cylinder - Hydraulic system self-adjusts for pad wear - Compatible with all mechanical road and CX brake levers - Brake pad composite is Resin with Metal Fibers - Resin with Metal Fibers pads are compatible with Resin-Only type rotors as well as standard rotors