M3 stylus for Metrol probe system with 4.0 mm diameter ruby ball, 2.0 mm diameter carbide stem, and 5.0 mm diameter x 7.5 mm long stainless steel base. Ds = 2.0 mm, L1 = 43.0 mm, L2 = 35.5 mm. Stylus weight is 2.47 grams. Compare to Metrol F-R40T-405.