FRONT CHAINWHEEL, FC-R8000, ULTEGRA, FOR REAR 11-SPEED, HOLLOWTECH-2, 170MM 50-34T, W/O BB

Optimized lightweight crank arm design produces excellent power transfer efficiency
HOLLOWTECH II
Redesigned FC for greater frame compatibility
Rider tuned gear performance through various gear combinations
Wider gear pitch increases clearance between chain and leading teeth to provide compatibility with frames with O.L.D. 135mm and 410mm chain stay length