This handcuff key extension tool with swivel is 3-7/8" long with key. The handle enhances use of the original key. It gives a standard key that is easily replaceable an extended length and solid grip. The swivel feature allows the user to manipulate the key by rolling the barrel between the thumb and forefinger. To replace the key simply unscrew the end cap and insert a new key. Includes 1 key and keyring.