SRAM XX1 Eagle AXS Crank Arm Assembly - 170mm 8-Bolt Direct Mount DUB Spindle Interface GraySRAM XX1 Eagle AXS Crank Arm Assembly 170mm 8 Bolt Direct Mount DUB Spindle Interface Gray. The SRAM XX1 Eagle DUB crank arm assembly offers simplicity compatibility and durability in a Carbon Tuned package. DUB technology simplifies the relationship of the spindle to the bottom bracket 8 bolt crank interface is compatible with Quarq Dzero XX1 Eagle power meter spider Not compatible with SRAMs 3 bolt direct mount interface Spider and chainrings sold