Without wires or cables, SRAM designed a simpler way to shift with the nearly flawless RED eTap, and now, the intuitive simplicity of the eTap system is available with the added performance of hydraulic road disc brakes (HRD). The SRAM RED eTap HRD shift-brake control offers the world’s first wireless drivetrain with SRAM's most advanced HRD platform yet, HydroHC. Simpler shifting, better braking—all in the name of true advancement. - Easy to install on any frame; compatible with all SRAM road 22 speed cranks, cassettes and chains. - Includes two 160mm Centerline two-piece six-bolt rotors In the Box: - Red eTap Front Derailleur w/ Battery - Red eTap Rear Derailleur w/ Battery - Red eTap HRD Right Shifter with Caliper - Red eTap HRD Left Shifter with Caliper - eTap Battery Charger and Power Cord - USB Stick and QuickStart Guide