SRAM Rival AXS XPLR E1 Rear DerailleurSRAM Rival AXS XPLR E1 Rear Derailleur Perfect shifting through better design, even through the toughest gravel terrain. By using a Full Mount interface, the Rival XPLR AXS rear derailleur ensures perfect shifting with no adjustment screws, and unmatched resilience to whatever the world throws at you. Mud, loose rocks, or careless airline employees cant knock this out of adjustment. Wireless AXS shifting pairs with our smooth and strong chain