Cast Iron Window Stop in a vintage iron finish. This window stop is designed to hold widows open that will no longer remain up by themselves. Old windows with broken sash cords or missing weights can now be held open without using sticks or props. To install, position and secure the lower sash in the desired open position. Position the stop on the side jam so that the hook portion is securely under the bottom of the lower sash. Mark the location of the screw hole and drill a 3/32” diameter pilot hole. Screw the stop to the side jam. Carefully make sure the stop will hold the window in the open position and not slip out. If trim or the window track does not allow the stop to be mounted flush with the side jam, a wood shim or spacer is required. Such a spacer is firmly attached to the side jam and then the stop is screwed into the spacer. See the drawing below.