Every reloader should know exactly how much your Full Length Sizing Die is pushing back the shoulder. With the L.E. Wilson Case Gauge Depth Micrometer you can do just that! It has never been easier to measure your case's headspace before and after sizing. The Depth Mic allows you to slip the micrometer perfectly over the top of the gauge with your case inserted into the gauge and take a measurement. Package includes Depth Micrometer and a Gauge Block which can be used to re-zero the Depth Mic if needed. One size works for all L.E. Wilson Gauges.