Like its predecessors, the Shimano CN-HG901-11 Dura Ace 11 Speed Chain features a slight asymmetry to allow it pair perfectly with Shimano's 9000-series drivetrain for smooth gear shifts and excellent power transfer. With Shimano's groundbreaking SIL-TEC low friction treatment, this chain glides through the cogs with minimal friction, so you can focus on the smooth climb, rock-lined single track, or bike lane ahead with a chain you can depend on.