This gauge has several unique markings to it. Made by Jas P. Marsh Corporation Chicago who supplied the USN with there pressure gauges. This particular gauge has a hand script plaque dated 8/29/44 in the lower center of gauge that also says," #1 Tube Torp.room. ". The plate itself is held in by two slotted screw and not Phillip heads which predate the late 40's and early 50's.They also look machined into place. Gauge is 6 1/2' in diameter with a straight brass fitting at the bottom. The face plate and body are most likely Bakelite and the face is a screw off. Their are two offset slotted screw with one marked Recalibrator and the smaller marked Lock. Both of these screws show a bit of wear.