Use a Cotter Pins to tighten the lock nut or fix the U-shaped pin. Cotter Pins distribution is difficult to introduce and eliminate and is usually used to fix wheels or machines on axles in sections. The Cotter Pins has two long prongs, twist it to keep it in place. Fastener cuts (also called r cuts) are designed to slide without twisting. Keep Grainger separation pins close to quickly follow up and repair the hardware.