e*thirteen spared no expense creating the Helix R e*spec Chainring. Designed for Bosch Gen 4 e-bikes, this 1pc direct mount chainring is forged from 7075 AL for stiffness, strength and the longest wear life. The extensive CNC machining and M3 tooth profile delivers an ultra lightweight upgrade chainring that offers the best cross compatible Shimano/SRAM chain retention and eye-catching technical aesthetics. A custom outer dust cover enhances the integrated style and helps to preventcontamination.The Helix Race E*spec Ring is fully compatible with Shimano, SRAM, and TRP 11 and 12 speed drivetrains, and comes in Black, Bronze, Eggplant Purple or Naranja Orange for color coordination with e*thirteen cranks, cassettes, stems, tubeless valves and more. Available with 53mm chainline in 32T and 34T sizes, it supports dropping a chainring size to take full advantage of e*thirteens proprietary 9T smallest cog, wide range cassettes.Chain Reaction: 53mmCompatibilityBosch CX Gen4 MotorT-Type Chai