Easton Direct Mount CINCH Chainring For Flattop Chains SRAM's new Flattop chains require a specific chainring to work properly. The Easton Direct Mount CINCH Chainring is designed for Flattop chains and has an updated tooth profile optimized for SRAM Flattop 12-speed chains. They use a narrow/wide design specifically tailored to road/CX/gravel applications. The individual tooth profile has moved from the traditional symmetrical shape to a more directional specific design to create a positive chain roller engagement to help with chain retention, critical to prevent chain slippage and bounce over rough terrain. Features CINCH direct mount system provides weight savings and makes swapping chainrings fast and simple Optimized for 12-speed Flattop chains Directional tooth design provides exceptional chain retention Crafted from EA90 Aluminum Compatible with 11-speed chains but is not optimized for them, so your performance may vary SPECIFICATIONSDrive Train Speed12-Speed Flattop Tooth Count40T, 42TMaterial EA90 Aluminum Direct Mount Type Cinch Chainline47mm Offset-Intended Use Road, CX, Gravel Weight N/AChainline/Chainring Offset Guidelines Rear Spacing135mm / 142mm148mm Boost Super Boost 150mm / 157mm Fat Bike (170mm, 190mm, 200mm)Chainline48 - 50mm51 - 53mm54 - 56mm56mm+Chainring Offset~6mm~3mm~0mm~+2mm | Easton | Direct Mount Cinch Chainring Dm, 40T, 12Spd, Flattop Blk | Aluminum