Crank description: Brand: JIANKUN (IXF) Crank Arm length: 170mm Material: AL6061 aluminum alloy Compatible: Single/Double/Triple chainring; for 7/8/9/10/11S chainring Bolt Center Diameter: 104mm BCD Weight: about 637g (right & left) Advantages: light weight,stylish appearance,very cool,high strength axle,strong compatibility Bottom Bracket description: Brand: JIANKUN Size: 41*24*24mm( threaded) Spindle/Bearing inner diameter: 24mm Fit BB shell width: 68/73mm Fit BB shell inner diameter: 1.37in x 24 TPI Spindle Interface Type: Hollowtech II Chain line: 48.5mm Bearings: Sealed (3 spacers included) Hollow axle, one piece external bottom bracket for MTB/Road bike,folding bike refitting Suit for Shimano, FSA compatible. Giant ATX770 ATX770-D XTC750 and so on.