Checkline DM-830 [DM-830-D] Analog Metric Dial Thickness Gauge, Range 0 - 25 mm, Jaw Depth 300 mm, Feeler D (5 mm) For Rubber Rings, Round Material. Measuring Range: 0 - 25 mm, Resolution: 0.1 mm, Jaw Depth: 300 mm. The analog dial thickness gauge DM-830 determines the thickness of various materials, like leather, textiles, cardboard, felt, rubber, sheet metal, foil, plywood, plastic, etc. This thickness gauge is self closing and guarantees high accuracy and resolution.