Shimano GRX C/SET GRX RX820 42T single 12spd 170mm

The SHIMANO FC-RX820-2 balances weight savings and optimal efficiency for mixed-terrain riding and racing. Double chainring gearing caters to the segmented demands of gravel cycling, maintaining the tighter gear steps needed to maintain your position in the bunch. The 2x12-speed crank utilizes a 48-31T chainring and comes in 170, 172.5, and 175 mm crank arm lengths. Features:- Smaller gear steps for cadence control on mixed-terrain riding- Gravel-optimized gear ratios preserve riding rhythm on rough surfaces- Wider gear range- 17T range covers array of riding conditions- Gear combination: 48-31TSpecifications:- Rear Speeds: 12-speed- Rear Speeds: 12- Crank arm length(mm): 172.5- Chain Gurd: Without CG- Gear Combination: 48-31T- Recommended bottom bracket|Press-Fit: SM-BB72- Recommended bottom bracket|Threaded (normal): SM-BBR60- Compatible bottom bracket type|Outboard: X