M2 stylus with 0.5 mm diameter silicon nitride ball, tapered carbide stem, and 3.0 mm diameter x 6.0 mm long stainless steel base. Minor stem diameter is 0.3 mm; major diameter is 1.0 mm. Overall stylus length is 20.0 mm. Stylus weight is 0.33 gram. Compare to Zeiss 626102-5445-020.