It's made of hardened stainless steel. It measures from .001" to 6" or .01mm to 150mm. It calibratibles to zero, and can change from mm to inches with the touch of a button. It also has a locking screw, combined display, external measuring surfaces, thumb roller, rail, battery cap, depth measuring bar, step measuring surfaces and knife-shaped measuring surface for inside measurements.. It also in a molded and padded black plastic case for safe storage. It can be used for industrial work, hobby work, jewelry, gunsmithing, etc