Features: Two measurement method, magnetic induction for magnetic substrates such as iron and steel; eddy current method for substrates such as brass, aluminium, zinc etc. ; Highly sensitive probe, automatically identify the substrates Three measurement modes, single measurement, continuous measurement, fast continuous measurement; IPS High-definition large color screen with clear and easy reading, more settings of brightness, color, screen rotation; Built-in lithium battery, USB direct charging, eco-friendly and ; Multiple calibration modes (automatic probe calibration, manual zero calibration, manual multiple points calibration), better decreasing the measurement errors and secure the accurate measurement; 2S fast switch on, 50 data can be stored; high and low alarm value can be set Measurement principle: electromagnetic induction/eddy current effect Test range: 0-2000UM Error: ±(2.5%+2UM) Display accuracy: 0.1μM (0-99.9μM) 1μM (≥100μM) Unit: UM, MM, MILS Minimum convex curvature