Available for all steep taper tool holder sizes (20, 30, 35, 40, 45, 50, 55, 60) The tool holder inspection gauge is designed to inspect tool holder taper diameters for wear and other potential problems. Verifying tool holder tapers are correct can help to maximize spindle life and improve part finish. Please note that the taper inspection gauge will only check diameter on two planes along with taper angle. The gauge will not detect nicks or localized damage to the taper. We recommend using series 430.110 taper sleeve gauges in conjunction with the taper inspection gauge for this purpose. The tool holder taper inspection gauge includes the Fixture Base and two Indicators (0.002mm or 0.0001 inch resolution). An optional 430.110 certified Taper Master is strongly recommended for zeroing the Indicators. If a master is not available, a known good tool holder can be used in place of the master.