Abstract: Means are provided for retaining fire doors in the open position against the action of the spring or other automatic door closers, with remote control release which can be actuated if a fire is detected. In use, one part thereof is mounted on the wall and has gripper means for engagement with another part which is mounted on the door. The wall-mounted part also includes release means spring-biased into a first position in which operation of the gripper means is inhibited and pneumatically operated means for holding the release means in a second position in which operation of the gripper means is not inhibited.