During measurement, instrument automatically identifies the metal properties of the base material, screen shows "Fe", means base material is magnetic, steel, iron, etc; Screen shows "NFe",means substrate is non-magnetic material, aluminum, aluminum alloy, copper, etc. Short press the MODE key to select measure mode (Single/Continuous) After power on, press the power key briefly to select the measurement unit um/mil Support data clearing function When measuring, screen displays value, short press the MAX/MIN key to lock the upper or lower limit value. The device will lock the upper or lower limit value measured on the surface of the substrate after multiple measurements Place standard piece 50um/100um/250um/500um/1000um on iron base or aluminum base surface individually. When instrument probe contacts, corresponding calibration point should be displayed. If screen displays a large error with the placed standard piece, pressing CAL key is the same as zero point calibration Specifications: Type: CT02 Basic model Power: 1.5V x 2 AAA battery (not included) USB: No Weight: about 95g (excluding battery) Display: LCD Measuring base: Iron base or aluminum base Sampling method: Iron base: magnetic induction; Aluminum base: eddy current effect Measuring range: 0-1500um Resolution: 0.1um Accuracy: Iron base or aluminum base/±(3%+2um) Automatic shutdown: About 10 minutes Measurement mode: single/continuous Unit: um/mil The radius of the minimum convex curvature: 5mm The radius of the minimum concave: 50mm The diameter of the minimum measunng area: 20mm The minimum thickness of base material: Iron base or 0.5mm/aluminum base 0.3mm Working current: About 30mA Working environment: 0~50℃/0~80%RH