This steel digital caliper delivers excellent accuracy and features jaws that measure ID and OD from 0–102mm (0–4") with .025mm accuracy; it provides readings in inches and millimeters. The caliper has a resolution of .0005" (.01mm), and has a zero set button, making easy work of relative measurements. An easy-to-read LCD display features a one-button change-over from millimeters to inches. A thumb wheel and lock make it easy adjust to your desired measurement and lock it in to transfer that measurement to other materials. A protective case and battery (LR44) are included.