Digital Tube Thickness Caliper-Type Gage This versatile OD measuring gage is great for measuring hole diameters, groove thickness, tube thickness, and hard to reach dimensions. Provides error free LCD readings as well as data output. Features include... 0-1.97" / 50mm Measuring Range 0.001" / 0.02mm Resolution 0.0024" / 0.06mm Accuracy 6.57" / 167mm Max Measuring Depth 1.17" / 30mm Upper Contact Point Length 0.18" / 4.6mm Lower Contact Point Length 0.12" / 3mm Ball Diameter Upper & Lower Contact Points