The revolutionary four-arm spider and stiff Hollowglide chainring construction places the Shimano Dura-Ace 9100 compact crankset at a new industry standard with a low weight and rigid build. Its new chainring tooth profile has been adapted to be compatible with race bike specific disc brake systems. The Dura-Ace 9100 features a 24mm steel spindle axle, plus a choice between press-fit and threaded bottom brackets.Features: Enhanced design shaved off 7g while maintaining rigidity Rider Tuned gearing options 11-speed compatible Hollowglide chainring construction Improved stiffness-to-weight ratio Accommodates bikes with disc brakes and short chainstays 24mm steel spindle axle Compatible with press-fit and threaded bottom brackets