Mitutoyo Disc Micrometer Disc flanges on micrometer make it possible to get accurate measurements on areas not reachable with standard micrometers such as gear pitch, ribs, slot and groove distances. Features Include... 75-100 Measuring Range 0.01mm Graduation + 6um Disc flange dia.: .787" / 20 mm Ratchet Stop for constant force Lever lock Furnished in fitted case