Opening damper FD115 Helps to prevent the door and door handle from hitting a return wall. Simple fitting into guide rail and continously adjustable. Does not replace a door stop. Can be used only with G464 on active leaf. Specifications Type of product Close Connecion box FD145Connection box for door leaf installation. Sliding arm FD499Sliding arm with free-swing function for door closers. Connecion box FD140Connection box for door leaf installation.