E. Suydam and Co. 6x9 120 Roll Film Back for 4x5 view CamerasE. Suydam and Co. 6x9 120 Roll Film Back for 4x5 view Cameras. It appears to function properly, but has not been tested with film or a camera. There is no guarantee that there are no light leaks. The dark slide functions properly. The two red film number viewing windows appear to be fully intact. To total size of the mounting area of the back is 6 5 16" long x 5" wide. On each side of the back there is a bevel with a 5mm width and 1mm depth. The