The Red XPLR eTap AXS rear derailleur is a dedicated 1x-specific unit designed for use with the XPLR 10-44 cassettesWireless electronic eTap shift logic for intuitive shifting, easy setup and reliabilityLarger X-Sync pulleys with ceramic bearings for increased durability and efficiencyOrbit chain management technology keeps the drivetrain quiet and secureSram AXS enabled, allowing easy personalizationCompatible with existing eTap batteriesRed XLPR eTap AXS12sp44tLongBLKUPC/EAN/GTIN: 710845868962