Digital ABS Bore Gauge 511-521 Range 45-100mm/1.8-4"A Mitutoyo ABSOLUTE Digimatic bore gauge designed exclusively for ID measurement. A minimum value holding function provides easy measurement of hole diameter. Up to three sets of master value and upper lower tolerance values can be memorized and recalled at the push of a button. An analogue bar indicator is integrated to enhance ease of reading, especially for GO NG judgement. Measurements can be made inside very deep holes by using up to four