This is an XRAY Delrin Shock Piston Set. These shock pistons are made from Delrin and molded using super-precise molds. There are 2 types of pistons with 2-holes, and different diameters for precise shock adjustments.
Available with different-sized holes for changing damping: 1.6mm, and 1.7mm holes. For custom adjustment, a set of blank pistons are also included.