key-fob

A keychain ( ) (also keyring) is a small ring or chain of metal to which several keys, or fobs can be attached. The terms keyring and keychain are often used interchangeably to mean both the individual ring, or a combined unit of a ring and fob.
The length of a keychain or fob may also allow an item to be used more easily than if connected directly to a keyring. Some keychains allow one or both ends to rotate, keeping the keychain from becoming twisted, while the item is being used.

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