Precision machined heavy duty alum rear clamping 8.5mm hex set designed for the PRO2 SC10, RB10, SR10, B5, DR10, DB10 and similar platform Associated cars. Precision hex shape to prevent stripping of the nylon wheels and stays put when your swap out the wheels. Looser steel cross pin tolerance allows you to tighten the wheel nuts without binding the bearings. The hexes do not lock onto the bearings, unlike the stock plastic hexes. Uses heavy duty M2 alum steel screws for the clamping (do not over tighten). 1 pair with M2 hardware.