A collet is a type of clamping device used to hold an object, typically a tool or workpiece, securely in place. It is commonly found in machinery and tools, such as lathes and milling machines, where precision is essential. Collets are designed to grip cylindrical objects and can be adjusted to accommodate different sizes. Collets come in various shapes and sizes, with the most common being the ER collet, which is widely used in CNC (Computer Numerical Control) applications. They provide a strong grip while allowing for quick changes of tools, making them popular among machinists and hobbyists alike.