Electronic digital gemstone gauge. Uses EBAT357. Range 000.00 mm to 025.00 mm. Zero reset button. Auto shut off when placed in case slipper measuring platform wedge-shaped points fixed rod.he Dial Gauge is an enhanced version of the traditional Leveridge gauge, featuring coded dual measurements in millimeters and carats. Measurements from 0.0 to 23.0 mm in 0.1 mm divisions. Includes gemstone weight estimation tables. One year warranty.