Shimano FC-R9200 Chainring Gear up Shimano's new Dura-Ace 12-speed drivetrain features a wide range of gearing options and configurations. With the FC-9200 chainring you can easily upgrade and alter your existing Dura-Ace 9200 crankset to fit your riding style and needs. The outer chainring models feature cutting edge Hollowglide tech which shaves off weight without affecting the chainring strength, thus maintaining excellent power transfer and precise shifting. Features Hollowglide tech saves weight while still delivering terrific shifting performance and power transfer New 54-40t combination for maximum speed Drivetrain speed: 12Outer chainring options: 54t, 52t, 50t Inner chainring options: 40t, 36t, 34t4-bolt Asymmetric pattern110 BCD | Shimano | Dura-Ace Fc-R9200 Chainring 52T | Aluminum