Variable tuning set for original variators and almost all tuning variators. The Speed-up shims can influence the length of the sleeve: an extension usually improves the acceleration and shortening increases the top speed. Before installation, be sure to measure the length of the original sleeve and then change the size of the speed-up sleeve with the washers accordingly! Kit contains the open racing variator sleeve and 15 spacers, each with 5 discs with 0.1, 0.2 and 0.5mm thicknesses. Sleeve size: 16x21x37. When using on tuned variators, please measure the diameter of the sleeve, which should be 21mm.