M3 Therm-X stylus with 1.0 mm diameter ruby ball, stepped carbide stem, and 5.0 mm diameter x 9.0 mm long titanium base. Minor stem diameter is 0.8 mm, major diameter is 1.0 mm. Overall stylus length is 35.0 mm. Stylus weight is 0.82 gram. Compare to Zeiss 626113-0100-035.