XX1 Eagle AXSThe Eagle AXS derailleur is the brain of the whole AXS system Shorter cage for 10mm more ground clearance, with more chain wrap on the cassette to sit slightly further forward, and further inboard from mechanical Eagle Battery not included SRAM Model ID: RD XX 1E A1 Attributes Maximum Cog 52T Minimum Cog 10T Primary Color Black Cage Long RD Capacity 40T Speed 12 Mount Standard