Shimano BR-R451 Road Brake Calipers FEATURES: Compatible with STI and brake levers that are Super SLR enabled (e.g. Dura Ace Di2 7970, Dura Ace 7900, Ultegra Di2 6770, Ultegra 6700, 105 5700, Tiagra 4600) Light action and accurate brake power Adjustable toe-in brake shoes Use of these calipers with standard SLR enabled STI and brake levers results in a "mushy" brake response SPECS: Brake Mount Type: Mid Reach Caliper (47mm - 57mm) Brake Lever Actuation: Short Pull Super SLR Pad Type: Cartridge