Model ID: RD-RED-E-A2 . SRAM eTap shift logic and wireless operation . Fits all 11-speed SRAM road cassettes up to 11-32t . 2x and 1x compatible . Updated version of the original SRAM RED eTap rear derailleur . Orbit chain management technology keeps drivetrain quiet and secure . Larger X-SYNC pulleys and ceramic bearings for increased durability and efficiency . Compatible with existing eTap batteries
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