Measure holes and edges on sheet metal and other thin materials. The straight edges on these cylindrical styli maintain stable contact with thin materials better than the curved edges on a ball styli. However, they’re not as precise as ball styli. When they touch a workpiece, they trigger your coordinate measuring machine (CMM) probe to send a signal and measure geometric features. They’re often used with touch-trigger probes.

As a rule of thumb, you should use a stylus with the shortest length that works for your application. If a stylus is too long, it’s more likely to move farther than it should, reducing measurement accuracy.