Prime‑Line® cotter pins provide a simple, reliable way to secure nuts, bolts, and mechanical components in place, helping prevent loosening caused by motion or vibration. Commonly used with castle nuts, clevis pins, and slotted fasteners, cotter pins are ideal for automotive repairs, lawn and garden equipment, trailers, furniture, and general hardware applications. Designed to insert easily through pre‑drilled holes and bend into position by hand or with pliers, Prime‑Line cotter pins create a dependable locking solution without the need for specialized tools. Manufactured from quality materials for strength and durability, they are intended for use with same‑size matching fasteners to ensure proper fit and secure performance. Trusted by DIY homeowners and professionals across the U.S., Prime‑Line cotter pins make it easy to complete repairs and assemblies safely, confidently, and efficiently.