This is a straight stylus that can be used for simple features with which direct contact can be made.
The carbon fibre stem on this stylus is very lightweight so is ideal for use where weight is an issue.
The ruby tip is very hard wearing and is ideal for most standard applications.
A silicon nitride tip is recommended if you are scanning aluminium as particles will not be deposited on the surface, unlike with ruby.
Zirconia tips are more suitable for abrasive surfaces, such as cast iron parts.

Renishaw Styli A-5003-2289 M2 ø4 mm ruby ball, carbon fibre stem, L 100 mm