Rival XPLR eTap AXS, Rear Derailleur, Speed: 12

* Wireless electronic eTap shift logic for intuitive shifting, easy setup and reliability* 1x specific for use with 10-44 XPLR cassettes and 10-36 cassettes* SRAM AXS enabled, allowing easy personalization* Chain management keeps the drivetrain quiet and secure* Larger X-SYNC pulleys for increased durability and efficiency* Compatible with existing eTap batteries (not included)* SRAM Model ID: RD-RIV1-E-D1