Electronic Thickness Gage This versatile OD measuring gage for hole diameters, groove thickness, tube thickness, and hard to reach dimensions. Make for fast, accurate, and repeatable measuring. Absolute & Relative Modes for MIN / MAX & Hold. Features include... 2" - 4" / 50-100mm Measuring Range 0.001" / 0.02mm Resolution 6.57" / 167mm Max Measuring Depth 1.17" / 30mm Upper Contact Point Length .9" / 23mm Lower Contact Point Length 0.196" / 5mm dia Ball on both tips SPC Output IP67 Rated Protection