Hope retainer narrow wide chainring the new retainer ring is designed to work without the need for a chain guide with the use of a clutch style rear mech no need for heavy chainguides noisy drivetrain and drag cnc machined 7075 t6 aluminium provides the perfect blend of light weight and strength the chainring is compatible with 9spd 10spd and 11spd set ups a hard anodised finish makes these ultra durable and increases longevity available in 104mm pcd 4 bolt fitting specification avai