- 50mm chainline for GRX cranks only. Fits RX600 and RX810 - Road/Cyclocross/Gravel ring with Drop-Stop B tooth design to prevent unwanted chain drop - Drop-Stop B fits all 9, 10, and 11spd chains or 12spd SRAM Eagle, SRAM Flattop, Campagnolo, KMC, Connex or Wippermann chains - Designed and manufactured in the USA from 7075-T6 aluminum alloy