Hardened stainless steel body. Switches and displays from inches to millimeters with the touch of a button. Range of 0-6"/0-150mm. Accuracy: +/-0.001"/0.01mm. Resolution: 0.0005"/0.01mm. Adjusts to zero at any position. Measures internal, external, depth and step dimensions. Jaw depth measures 1-1/2" outside and 5/8" inside. Lock holds slide in position for measuring constants. Low battery indicator. Fitted plastic storage case and 1.55 Volt SR44W battery (included).