CHARACTERISTIC Made of extra strong carbon fiber composites, Light weight and durable to use; Widely range of usage: a teaching tool, familial tool, a tool of carpenter, in the laboratory, in the breeding farm, etc; Unique switch design, flexble and efficiency; FUNCTION ZERO: Zero setting anywhere ON/mm/in: Metric/inch system conversion and power on OFF: Manual power off Auto Power Off TECHNOLOGY PARAMETER Range: 0-150mm/6" Resolution: 0. 1mm/0. 01" Accuracy: 0.2mm/0.01" INSTRUCTION Keep body faces clean, prevent liquid from getting into the slider for fear of damaging the electronic. Faces should be cleaned gently with alcohol or other cleaners. Never use other organic solution and never clean caliper by immersing it in any liquid. Never apply any voltage on any part of the caliper and never use an electric pen in case of damaging its core. Power: a single 1. 55V silver oxide battery operation and flashing display warn for battery.