The 600 G/GF cylinder locks with gear mechanism are part of the series 600 mechanical locks for armoured doors. They are equipped with a special gear mechanism designed to allow the key to turn smoothly, without force. The deadbolts have an anti-cut reinforcement and the following 2 additional features can be added: a deadbolt self-locking system if the cylinder breaks and the option to secure the cylinder with a frontal screw. If the key is lost or stolen, the owner can change the cylinder and restore security quickly and easily without having to replace the whole lock.