Instant reading. Very easy to use. Hardened stainless steel body for prolonged tool life. Switches from inches to millimeters with the touch of a button. Range of 0-6"/0-150mm. Accuracy +/- 0.001"/0.02mm. Resolution: 0.0005"/0.01mm. Large, easy to read numbers, reduces error – no guessing. Adjusts to zero at any position. Measures internal, external, depth and step dimensions. Jaw depth measures about 1-1/2" outside, 5/8" inside. Lock holds slide in position for measuring constants. Battery included. Low battery indicator. Fitted plastic storage case. Imported.