The Shimano Steps SM-CRE70-12 chainring w/Chain Guard (Double) 50mm Chainline 42T for the Shimano STePS E8000 E-MTB drivetrain system features a modern design. The 12-speed chainring is compatible with the FC-E8000, FC-E8050, and FC-M8050 crank arms. B.C.D.: 104 mm.