RaceFace Race Chainring, 58mm, 20T, Silver CNC machined in our British Columbia, Canada manufacturing facility. Outer, middle & aluminum inner rings manufactured from 7075-T6, one of the strongest alloys available today. Outer rings are made from 4mm thick material & middle rings from 5mm thick material for unsurpassed durability. Rings feature our patented S.H.I.F.T. technology, featuring hardwearing steel S.H.I.F.T. chips for dual action up-shifts.