SHIMANO SORA BR-R3000 Dual Pivot rear brakes - better braking power and performance for entry level riders. Good balance between stiffness, weight and braking power. Assembly pivot nut: rear 10.5mm Brake shoe: R50T5 (Standard for aluminum rim) Reach: 51mm Rim width: 19-28mm Maximum tire size: 28mm Material: Aluminum DUAL PIVOT design realized a lightweight, compact and durable braking system. Dual-Pivot Caliper brake have made considerable progress in reduction of tolerance and deflection as well as in durability. They have achieved firm and instantaneous braking response while assuring longer service life. Moreover, the brake pads have an improved durability of 100% to help enjoy high-response braking over longer periods. NEW SUPER SLR - design makes use of a friction-reducing mechanism in the caliper, lever and cable that improve response and modulation. Also for the lever, the SERVOWAVE mechanism is adopted to provide quick contact of shoe to rim and longer stroke from the initial braking effect for better control. SLR is the essential factor in the SHIMANO dual-pivot caliper that deliver more braking power than conventional side-pulls.