The FastTune Camber Shims are made from aluminum and designed to allow you to easily adjust your camber on popular pillow ball designs without having to fully unthread them. The tab feature helps you keep them in place as you tighten down the pillow ball. Don't get caught up in all the complicated sizes AE has introduced, 0.5 and 1.0mm shims have been working for Mugen since the dawn of time.