M2 stylus with 0.5 mm diameter ruby ball, tapered carbide stem, and 3.0 mm diameter x 6.0 mm long stainless steel threaded base. Minor stem diameter is 0.3 mm; major diameter is 1.0 mm. Overall stylus length is 22.0 mm. Stylus weight is 0.35 grams. Compare to Zeiss 626102-5444-022.