Measure inside and outside diamtere with this 6-Inch LCD Digital Micrometre Measuring Tool Measurement Range: 0-6”/0-150mm Resolution: 0.01”/0.1mm Accuracy: approximately 0.01”/0.2mm Can be used to measure inside and outside diameter As well as depth and step with two sets of jaws and probe Requires an LR44 battery (included) Inch to the millimetre and back conversion Zero setting function Large LCD screen Auto shutdown after 5 minutes of not using 4.99 pounds for the 6-Inch LCD Digital Vernier Calliper Micrometre Measuring Tool - save 62%