Coating Thickness Gage Main Technical Data... Measuring Range: 0-1000um max or 0-40 mils Guaranteed tolerance: +/-(2 um +3%) , +/-(0.1 mils +3%) Display: 3 digits (digit height = 15 mm) Min measuring area: 0.2" x 0.2" (5mm x 5mm) Min radius of curvature: Convex: 0.12" (3mm), Concave: 1.2" (30mm) Min substrate thickness: Ferrous: 20 mils (0.5mm), Nonferrous: 2 mils (50um) Calibration: zero calibration, foil calibration Max surface temperature of test object: 302 degrees F (contact time max is 2 seconds) Memory: 10 measurements Power Source: 1 AAA battery Dimensions: 4.25" x 1.80" x 0.885" Weight: 2.7 oz The SPI coating thickness gage can perform two different methods of calculating thickness measurement by utilizing the characteristics of both eddy current and magnetic induction. Testing performance is both nondestructive and extremely accurate. This sleek state of the art thickness gage easily detects the thickness of nonmagnetic coating on a magnetic substrate (ferrous) or an insulating coating on a non-magnetic conductive substrate (nonferrous). Can be used in many areas of industry including automotive, manufacturing, general engineering, commercial inspection, etc. Flip display for reading upside down. Package Includes... Main Unit 2 Substrate Samples (steel, aluminum) 4 Calibrated Thickness Samples Operation Manual Batteries Carrying Case