M3 stylus with 0.5 mm diameter ruby ball, tapered carbide stem, and 4.0 mm diameter x 10.0 mm long stainless steel base. Minor stem diameter is 0.3 mm; major diameter is 1.0 mm. Overall stylus length is 21.25 mm. Stylus weight is 0.89 gram. Compare to Zeiss 602030-8115-000.