Central Tools 4346 Dial Indicator, 0-100 Reading, 0-.200" Range, 0.001" Graduations, Back Plunger, 1/4" Shank. Part Number: 4346. The Central Tools 4346 Dial Indicator is also known as a precision dial gauge, back plunger indicator, machinist's dial indicator, 0.001" graduation dial indicator, and jeweled bearing dial indicator.