See: 1up Racing

1up Racing have introduced five sets of precision aluminum shims. The precision aluminium shims are cut on a CNC lathe to strict tolerances before receiving their beautiful glossy black anodized finish. Use these with M3 screws or ball studs, or with any 3mm pins to ensure accurate settings every time. The precision aluminium shims are available in 0.25, 0.5, 1, 2 and 3mm thicknesses, 12-piece per bag.