TM4-6053-C / M4 Machine Tool Probe Stylus with 6.0 mm Ruby Ball and Ceramic Shaft, 50 mm Long
Amazon.com Price: $79.99 (as of 12/27/2020 20:45 PST- Details)
M4 stylus with 6.0 mm diameter ruby ball, 4.5 mm diameter ceramic stem, and 7.0 mm diameter x 10.0 mm long stainless steel base. Stylus length to ball center is 50.0 mm. Stylus weight is 4.68 grams. Compare to Renishaw A-5000-3709.