The Shimano FC-RX820-1 crankset offers a balanced combination of weight savings, optimized efficiency, and a range of gearing options that meet the diverse demands of mixed-terrain riding. By pairing a 10-45T or 10-51T cassette with a 40T or 42T chainring, the rider can choose between closer gear ratios or the ultimate range. The FC-RX820-1 is available in crank arm lengths of 170, 172.5, and 175 mm, providing an additional level of customization.