Premium Material: Made of Plastic, won’t scratch your valuable objects when measuring, serve you for years. Accurate Reading: Strictly tested to ensure exact measurements which accurate to 0.01 inch. Zero Calibration: Press to set to zero at any position and continue to measure next section. Unit Conversion: Easy to read in inches and mm by pressing the blue button on the top. Large LCD Display: Shows instant readings with digital numbers, much more convenient. Auto On/Off: Auto turns on when sliding, auto turns off after 5mins if with no operation. External Measuring: Measuring the outer diameter of objects with the long jaws. Internal Measuring: Measuring the inner diameter of objects with the top jaws. Depth Measuring: Measuring the depth of hard-to-reach small objects with the long probe. Step Measuring: Measuring the height/length with its step design. ● Display: LCD screen ● Color: Black ● Power: one Battery (included), LR44 1.5V ● Measuring Range: 0-150 mm / 0-6 inch ● Resolution: 0.1 mm / 0.01 inch ●Package: 1 x Digital Caliper + 2 x LR44 Batteries 1. The digital caliper is only for household measurement, such as jewelry, gadgets and other household objects. 2.If for industrial measurement, please buy a more professional and more accurate measuring tool in professional field. 3. If you find the readings are not accurate, please slide the LCD screen to the left end (“0” on the scale), and then press the zero button. Welcome to write to us for more questions. 4. The battery compartment is securely fastened with a screw, which is on the back of the digital caliper, please use a screwdriver to unscrew it.