SRAM RED eTap Rear Derailleur - 11-Speed, Short Cage, Black, A2The SRAM RED eTap rear derailleur wirelessly executes shifts the instant you demand. It's easy to set up, clean in appearance and delightfully uncomplicated. Mechanical necessities such as a carbon pulley cage, ceramic pulley bearings, and anodized alloy artfully blend with proprietary electronic advancements to deliver a shifting wonder. SRAM eTap shift logic and wireless operation 2x and 1x compatible Orbit chain management technology keeps