The SRAM RED eTap 11-Speed Rear Derailleur offers precise and instant shifting, all done wirelessly. This derailleur is simple to set up and has a sleek look. It combines a carbon pulley cage, ceramic pulley bearings, and anodized alloy with advanced electronics for smooth gear changes. Features Wireless operation with SRAM eTap shift logic Compatible with all 11-speed SRAM road cassettes up to 11-32t Works with both 2x and 1x setups Updated design from the original SRAM RED eTap 11-Speed Rear Derailleur Orbit chain management for a quiet and secure drivetrain Enhanced durability and efficiency with larger X-SYNC pulleys and ceramic bearings Compatible with existing eTap batteries Battery not included Specifications Speed (RD): 11s Cable pull ratio: n/a Cage (RD): Short Max tooth: 33 Color (RD): Black Pulley bearings material: Ceramic Cage material (RD): Carbon