M2 stylus with 0.3 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 0.2 mm, major diameter is 1.0 mm.  Overall stylus length is 10.0 mm.  Stylus weight is 0.21 gram.  Compare to Renishaw A-5004-2016 and Zeiss 626102-5245-010.