The Redding Case Neck Gauge provides a quick and accurate way to sort cases by concentricity. Large dial indicator calibrated in increments of .001" allows you to accurately determine case neck uniformity, a requirement for precision reloading. Includes large 3/16" diameter mandrel and small 9/64" diameter mandrel for use with .060" flash holes. A separate pilot stop is required for each caliber - comes with 22 caliber and 30 caliber pilot stops. Stops for other calibers available below. Each pilot stop is CNC machined stainless steel, slightly undercut for a snug fit in the case mouth and smooth accurate indicator readings. Mfg: Redding