Hot racing multi-width hex adapters fit many 1:10 scale models with 12mm hex drives, and 5mm axles. Features: conk 6061-t6 aluminum construction widen 15, 20, 25 or 30 mm (per side) black in color you will receive: four light weight 15mm hex adapters four 15mm hex Adapter four 5mm hex Adapter four heavy duty hot racing wheel washer four 15mm cap Screw four 25mm cap Screw four O-ring four lock pin four 5x8 Shim requirements: 2.5mm Allen driver specifications: length: 15 and 20 (mm) hex size: 12mm inside diameter:4.58 mm.