Check the listing for details. Seneca DF500 Imperial Thickness Gauge. Condition: New. Listed at 41.48 USD. Seneca DF500 Imperial Thickness Gauge, 865553, Made of 3D printed polymer, Direct replacement for the metric gauge included with your DOMINO DF500, Centers on nominal lumber thicknesses, Designed to center on 1/2", 5/8", 3/4", 7/8", 1", and 1-1/8" nominal plywood thicknesses (undersized from dimensional lumber), The Seneca Woodworking Imperial Thickness Gauge for the DOMINO DF500 allows you to quickly and effortlessly adjust the DOMINO fence offset to center your mortise on a variety of imperial material thicknesses. The gauge installs in less than a minute using a Torx T10 bit (not included), and is a direct replacement for the metric thickness gauge included with your DOMINO DF500. The Imperial Thickness Gauge is designed to center on 1/2", 5/8", 3/4", 7/8",.