The e*thirteen Helix Race 107 BCD Chainring, designed for 4-bolt 107 BCD cranks like SRAM Red or Force including power meter equipped cranks, offers a performance upgrade for Gravel and Road cyclists. The 38, 40, and 42 tooth rings pair perfectly with e*thirteen’s cassettes for more overall range and higher top speeds. Made from durable premium 7075 alloy, they're CNC sculpted for a high stiffness-to-weight ratio. Compatible with both SRAM and Shimano 11 and 12-speed drivetrains. Chainline is set by SRAM® Crank assembly. Compatible with 4-bolt 107 BCD SRAM® cranks and Quarq® power meter cranks M4 narrow-wide tooth profile provides Shimano and SRAM 11/12-speed chain compatibility (Including flattop chains), excellent chain retention, and reduced wear 4.8mm offset (Chainline is determined by SRAM® Crank assembly, 45mm for normal width cranks, 47.5mm for wide cranks) Forged from premium 7075-T7 aluminum, then extensively CNC optimized for light weight, and technical aesthetics Durable 7075-T7 construction for long wear-life, stiffness, and strength
