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 0.4 mm; major diameter is 1.0 mm. Overall stylus length is 10.25 mm. Length to ball center is 10.0 mm. Stylus weight is 0.31 gram.