The X1 is cold-forged for high strength and light weight, loaded with trickle-down features and includes an X-Sync chainring to minimize dropped chains. FEATURES: Crank arms use Open Core hollow forging technology Integrated spindle design is light, strong and reliable Fits 68 or 73mm bottom bracket shells 7075 Alloy X-Sync chainring has tall teeth with alternating profiles to hold the chain well and allow mud to clear SPECS: Number of Chainrings: Chain Retaining Single Color: Black Pedal Spindle: 9/16" Crank Intended Use: Mountain Crank Length (mm): 175 Chainline/Hub Compatibility: 135/142 MTB Hubs Rings: 32 Spindle Interface Type: BB30/PF30 Chainring BCD: Direct Mount SRAM BB Included: No