box-four-8-speed-wide-narrow-chainring-104bcd
box-four-8-speed-wide-narrow-chainring-104bcd, The Box Four Wide/Narrow chainring completes that package for the 1x8 system. It is the first 8 speed specific chainring designed to optimize chain retention when using 8 speed chains. The tooth profile and thicknesses are tailored to match the inside geometry of the unique Box Four chain.SUPPORT MATERIALView Prime 9 Drivetrain Compatibility ManualHow is the Ebike variant different?View Prime 9 Comparison ChartWhy Prime 9?