cotter pin
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Quick Summary
A cotter pin is a metal fastener, typically half-round and bent into a pin shape. Its ends can be flared after being inserted through a slot or hole to secure components.1
Cotter pins are used in various applications, such as preventing nuts from loosening on bolts and keeping pins in place. They are also used with clevis pins, which are fastening devices secured by a cotter pin inserted through a hole at one end. The split cotter pin is a common type of pin fastener used to keep machine parts aligned or fastened together.2
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