Digital calipers from MEC Reloading can be used to measure brass or finished cartridges with extreme precision and accuracy. The calipers have a locking screw to maintain specific measurements for quick measurements without sacrificing consistency. MEC Reloading Digital Calipers measure in both inches and millimeters. Measuring range: 0-6", 0-150mm Accuracy: A 0.001"/0.02mm Repeatability: 0.0005"/0.01mm The Digital Calipers are made in the USA, as are all MEC Reloading machines and accessories. Mfg: Mec Reloading