Abstract: An "arrest" handcuff has the usual ratchet and pawl mechanism for closing the wrist aperture. In order to deadlock the pawl a runner is shifted by means of a manual push-button so that a stump on the runner then overlies a nose portion of the pawl. To release the deadlocking and pivot the pawl clear of the ratchet the runner must be shifted in the reverse direction, which movement is normally blocked by a lever pack operating on a stump extending from the runner. A correct key, however, can lift the levers and turn the runner back so that a further stump carried by the runner engages a tail portion of the pawl to lift it from the rathet. If the option to deadlock the pawl is not taken up in any particular arrest situation the pawl still remains engaged with the ratchet under a spring bias and the correct key is still needed to perform a reverse movement of the runner to lift the pawl from the ratchet.