SRAM Omnium Track Bicycle Crankset w/GXP Cups The first external bearing track crank in the world Designed for all-out velodrome racing, but also at home as the ultimate fixie crankset Omnium features SRAM's strongest and stiffest alloy, 7050-T6 The 5mm thick 7075-T6 chainwheel is designed only for 1/2 x 1/8 chains Bottom bracket included, 825 grams