The SRAM XX1 Eagle DUB crank arm assembly offers simplicity, compatibility and durability in a Carbon Tuned package. FEATURES: 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 SRAM's 3-bolt direct mount interface Spider and chainrings sold separately ?SPECS: Number of Chainrings: No Rings, No Spider Included Pedal Spindle: 9/16" Crank Length: 175mm Crank Intended Use: Mountain Spindle Interface Type: SRAM DUB Drivetrain Speeds: 12 Chainring BCD: Direct Mount SRAM 8-Bolt BB Included: No