Made by Jims in the USA, this tool is used to clearance tappet blocks for high-lift cams. Tool will remove only the material needed to allow the tappet roller to clear the tappet block. Professional results in a manner of minutes. Can be used with 1984 thru 1999 Evolution Big Twins and 1986 thru 1990 Sportster engines, including aftermarket and S&S engines.