Secured with a retaining ring at either end, you can add and remove parts without having to take the pin all the way out. These pins are commonly used with rod ends, hydraulic cylinders, and other pivoting components. In addition to taking up less space than cotter pins, the retaining rings surround the entire pin, so bumps are unlikely to work it loose.

Unlike most cotter pins, which install by hand, you will need retaining ring pliers to insert and remove the included rings.