Right Nut Frame Disc FactorBlack anodized aluminum piece located at the end of the chainstay, where the rear wheel thru-axle and derailleur hanger thread. Valid for Factor boxes with through shaft. Right Nut Frame Disc FactorBlack anodized aluminum piece located at the end of the chainstay, where the rear wheel thru-axle and derailleur hanger thread. Valid for Factor boxes with through shaft.