The Thickness Gauge XL provides a larger reference surface for a workpiece to rest on when centering a cut vertically. It has a protruding tenon on the back side to keep it aligned with the vertical T-slot in the Template Holder Support Frame. It also features a non-marring top surface to protect your workpiece from scratches and dings. The change over only takes a few minutes and the existing thickness and reference gauges remain on the machine in the event that the thickness gauge needs to be moved out of the way for an operation.