M5 stylus with 4.0 mm diameter ruby cylinder, 2.0 mm diameter carbide stem, and 11.0 mm diameter x 10.0 mm long titanium base. Overall stylus length is 40.0 mm. Stylus weight is 4.99 grams. Cylinder styli are used for edge probing, for example, the edges of stampings or sheet metal. They are not suitable for high accuracy work because the spherical form of a cylinder is not as precise as a sphere. Please contact us with any questions about calibrating or using cylinder styli.