Wolf Tooth Direct Mount Chainrings for SRAM 8-Bolt Mountain Cranks are optimized for the new SRAM Transmission mountain groupsets and T-Type chains. These are for folks who have the latest SRAM T-Type Transmission groupset that want a different chainring size beyond stock offering or upgrade to a made in USA option with an optimized tooth profile for better performance. These direct mount chainrings will replace your existing chainring and spider or replace a direct mount chainring for SRAM T-Type Transmission cranksets and other SRAM cranks that use the 8-bolt standard. SRAM T-Type Transmission DUB Wide MTB cranksets use the 8-bolt direct mount standard Use Drop-Stop B for all SRAM Eagle, SRAM Road and Transmission (T-Type) Flattop chains, 9, 10, and 11spd chains or 12spd KMC, Connex, Wippermann, Campagnolo.