Mitutoyo Internal Dial Caliper-Type Gage For checking internal bores, recess diameters and grooves. Features include... 3.2" - 4.0" Measuring Range 0.0005" Graduations +0.0015" Accuracy Max Measuring Depth: 3.3" Max Groove Depth: 0.31" Minimum Groove Width: 0.06" Ball Contact Points: 1mm Radius Spring loaded opening Press Button for closing arms. Arms automatically open when button is released Unit is spring-loaded and makes point contact at constant measuring pressure
