Disc brake lever/rear derailleur kit for DURA ACE Di2 2x12V range and rear clamp. Includes: DURA-ACE ST-R9270 ergonomic dual control lever brings new levels of comfort and control to road cycling. With the most rapide wireless shifter on the market. Carbon fiber brake lever and titanium hardware. SERVO WAVE technology optimizes disc brake control: lighter, smoother lever action. Enhanced modulation thanks to a wider braking control zone. DURA-ACE BR-R9270 hydraulic calipers are the most compact ever made. MONO-BODY construction guarantees lightness and rigidity. Brake caliper: one-piece construction maximizes rigidity and reduces weight. Additional 10% pad clearance reduces the possibility of disc friction. Easy bleeding process. Hydraulic clamp with structure monobloc. Weight: 97 g. Recommended brake disc: RT-MT900.