From Sherco / Scorpa - OEM P/N 6351 - Clutch Pre-Charge shim washer as originally found on 2017-18 models. Fits between the clutch spring and the pressure plate. This 1.2mm washer (6531) makes for a fast acting clutch, with less slip, but with harder lever pull. The alternative 1.0mm washer (6680) makes for a slower acting, softer, clutch that is more likely to slip.