For measuring plate thicknesses, depressions and radii of curvature of spherical surfaces, for example, lenses. The device consists of a tripod with three steel tips which form an equilateral triangle. A micrometer screw with a measuring tip is recessed in the middle. Attached to the micrometer screw is a disc with circular divisions from 0 to 500 and a vertical scale with millimeter divisions from -10 to 15 mm at the tripod.

Specifications:
Measuring ranges: 0 – 25 mm and -10 – 15 mm