“VIPREKHO Digital Calipers 6 inch/150 mm - Electronic Vernier Caliper with Large LCD Screen, Inch and Millimeter Conversion Measurement - Inner and Outer Diameter Measuring Tool (Black)” ♫ Made of strong plastic carbon fiber composites, lightweight and durable. And it’s not scratching your valuable objects when measuring, serve you for years. ♫ External Measuring: Measuring the outer diameter of objects with the long jaws. ♫ Internal Measuring: Measuring the inner diameter of objects with the top jaws. ♫ Minimum scale to read is 0.1 mm / 0.01 inch, an ideal tool for a broad range of industrial and automotive applications ♫ "If the numbers goes wrong when using, please change a new battery, it will work normally again, this is not quality problem cannot open dispute if this happened" ♫ 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. ►Specifications: ♪ Measuring Range: 0-6 inches/0-150 mm ♪ Resolution: 0.01 inches/0.1 mm ♪ Repeatability: 0.01 inches/0.1 mm ♪ Maximum measuring speed: 1.5m/sec, 60 inch/sec. ♪ Measuring system: Non-contact linear CAP measuring system. ♪ Display: LCD display, minus sign “-”, 4 digits character, and “IN” sign for inch measuring unit. ♪ Power: One battery, SR44/LR44 1.5V or CR2032 3V ♪ Operating temperature: 0°C-+40°C ♪ Storage temperature: -20°C-+70°C ♪ Influence of humidity: not important within