The Omnium track crankset is the first external bearing track crank in the world. Designed for world-class track racing, the Omnium features our strongest and stiffest alloy; 7050-T6. The full 5mm thick 7075-T6 chainring was developed for use only with 1/2 x 1/8 chains. Reports from our test riders suggest that this is the stiffest crank they had ever ridden. [FEATURES] TOOTH COUNT: 48 CHAINRING BCD: 144 CRANK ARM LENGTH: 165mm or 170mm (see options) WEIGHT: 825g Bottom Bracket Included (Compatible with SRAM GXP Bottom Bracket only) Risk-Free Purchase - State Bicycle Co. offers FREE EXCHANGES* -If this item doesn't work out, we'll send you a return label and exchange for free!