pplication:used for measuring thickness and corrosion of pressure vessels,chemical equipment,boilers,oil storage tanks,etc.in industries of petroleum,shipbuilding,power station,and machine manufacturing. Model: CM8822 Operating principle: magnetic induction/eddy current (F/NF) Measuring range:0-1000um Resolution; 0.1/1 Accuracy: -+1-3%n or -+2.5um Min. measuring area: 6mm Min. sample thickness: 0.3mm Battery indicator: low battery indicator Metric/ imperial: convertible Power supply: 4x1.5V AA(UM-3)battery Auto power off Operating conditions:0-+45C(32F-104F),≤90%RH Dimensions: 160x68x32mm weight: 250g(not including battery) Optional accessories: other range 0-200um to 15000um