M3 stylus with 0.5 mm diameter silicon nitride ball, tapered carbide stem, and 4.0 mm diameter x 5.0 mm long stainless steel base. Major stem diameter is 1.0 mm; minor diameter is 0.3 mm. Overall stylus length is 12.0 mm. Stylus weight is 0.53 gram. Compare to Zeiss 626123-5445-012.