Product details Introduction: This tester is designed to not-destructively measure thisckness of non-magnetic coatings (including paint, enamel, plastic,epoxy, etc.) on iron, steel and aluminum. General Specifications: Conversion of public and imperial units Automatic calibration Compact and easy to carry Power-saving, auto power off Data-hold mode Ergonomic Design Ergonomic design, Easy to use "UNIT" Button Press the "UNIT" button to select dsired unit: mm or mil mil: A unit of length equal to one thousandth of an inch; used to specify thickness(e.g., of sheets or wire) mm: A metric unit of length equal to one thousandth of a meter Low Battery Indicator When the indicator appears on the display, the button cell is low and must be replaced immediately. "TEST" Button 1. Press the "TEST" button to turn on the tester. Press and hold down this button for about 1 second to turn off the tester. 2. Press this "TEST" button to delete the reading on the display, will show"--". PROBE Measuring probe of the tester. Before measurement, place the tester with its probe firmly and in a right angle against the surface to be tested. EM2271,SPECIFICATION Measuring Range 0.0 mm to 2.0 mm, 0 mil to 80 mil Accuracy 2% rdg ±0.1 mm, or 2% rdg ± 4 mil Resolution 0.1 mm/1 mil Power Supply 3V button cell, CR2032 or equivalent, �1pc Size 69�38�20mm Weight About 23g (including button cell)