Mitutoyo Electronic Internal Caliper Gage These internal caliper gages are designed for measuring Internal Diameters that might be difficult to get to. They are also often galled a Groove Gage because of their perfect design for measuring IDs on internal grooves. Features include... 0.59-2.56" / 15-65mm Measuring Range 0.001" / 0.02mm Resolution 0.0024" / 0.06mm Accuracy 7.4" / 188mm Max Measuring Depth Ball 0.06" / 1.5mm Radius LCD Analog / Digital Display IP63 Rated Protection SPC Output Function Include... Zeroset Preset Auto Power Off In / Metric Conversion Data Hold Min / Max Value Hold