Wolf Tooth Shimano 110 Asymmetric BCD Chainring - 38t, 110 Asymmetric BCD, 4-Bolt, Drop-Stop ST, For Shimano GRX Cranks,These chainrings are for Shimano GRX cranks. They feature Wolf Tooth's patented Drop Stop design for the best wear life, chain retention, and mud clearance. Drop Stop ST is specifically for the Shimano 12 speed Hyperglide+ chain, which is used by GRX 12 speed. Compatible with Shimano GRX cranksets including RX600 and RX810 Drop Stop ST is designed for Shimano Hyperglide+ and KMC 12 speed chains only Wolf Tooth s patented Drop Stop wide narrow tooth