e*thirteen Helix R Chainring - 30t, 11/12-Speed, 3mm Offset, SRAM 3-Bolt DM, BlackThe e*thirteen Helix Race 3 Bolt Direct Mount Chainrings, engineered for SRAM 3 Bolt crank systems, merge aesthetics with robust durability. e*thirteen's narrow wide tooth profile ensures compatibility with Shimano and SRAM 11 and 12 speed drivetrains. Manufactured from AL 7075 T6 aerospace grade aluminum, the rings are CNC sculpted to provide low weights. Elevate your 3 Bolt Cranks, diversify drivetrains, reduce weight, and bring a new aesthetic to