• It boasts wide-profile carbon composite crank arms that flare into a three-armed spider with a wide chainring contact area, all designed for a combination of minimum weight and maximum stiffness. The splined axle is tough chromoly steel, the chainrings are CNC-machined 7075 aluminium with profiling to ensure super-smooth shifting, and the chainring bolts are Torx headed aluminium. It's compatible with nine-speed
• You are buying this fantastic chainwheel & crank set complete with Bottom Bracket - Hollow carbon fibre arms with UD weave
• AL7075 stamped inner chainrings 42/27 teeth with ramps/pins for smooth changing - AL7075 Torx T-30 alloy chainring bolts - 
• Compatible with 9 speed MTB systems
• 1.37 24tpi threaded ceramic megaexo bb set BB-9200 - suit 68-73mm bb shell
• 3 bolt BCD 85mm (74mm between each bolt) - 
• 175mm crank arm - 
• 24mm axle
• Weight 730Grams approx (complete set)