1Fe--Magnetic substrate indicator: Steel / Iron 2NF--Non-magnetic substrate indicator: Copper / Aluminum 3Auto power off flag, auto power-off in 15 minutes with no-operation 4LCD screen display, convenient to read in a dim environment 5Accurate, fast and easy use with powerful function Description: The thickness gauge is used to measure the thickness of the plated and coated sheet on metal, such as paint, enamel, chrome on steel, paint and anodizing coating on aluminum, copper. The gauge takes the precision integrated probe, and uses principles of electro-magnetic induction and the eddy current effect, which automatically detects the attribute of substrates. Features: Fe--Magnetic substrate indicator: Steel / Iron.NF--Non-magnetic substrate indicator: Copper / Aluminum.Auto power off flag, auto power-off in 15 minutes with no-operation.LCD screen display, convenient to read in a dim environment.Accurate, fast and easy use with powerful function.Specifications: Probe FProbe NPrincipleMagnetic InductionEddy CurrentRange0-1300um 0-51.2mil0-1300um 0-51.2milAccuracy(3%+2um) (3%+0.08mil)(3%+2um) (3%+0.08mil)Resolution0.1um/0.01mil0.1um/0.01milCalibrationPoints: ZERO/50/100/250/500/1000umUnitsum, milminimum curvature radius convex: 1.5mmminimum curvature radius concave: 25mmminimum measuring area: Diameter 6mmminimum thickness of substrate0.5mm(0.02")0.3mm(0.012")Power1 x 9V battery (NOT included)Operation EnvironmentTemperature:0-40(32-104) Humidity:20%-90%RHColor: GreySize: Approx. 12 x 6 x 3cm / 4.72 x 2.36 x 1.18inchWeight: Approx. 258gPackage Included: 1 x Digital Paint Coating Thickness Tester 2 x Substrate5 x Standard Slice1 x User Manual 1 x Bag 1 x 9V battery (NOT included)