This is a unique porthole from a military ship from the early 1940s. It is very heavy and solid - rightfully so as it is designed to keep water from entering it's space. The porthole does have its thick backplate - (which helps to seal it and be watertight) and measures 11" in diameter and is 1/4" thick. The round center brass shaft is 6" in diameter and is 1 1/4" deep. This part usually goes into/through a wall-type structure. There is a number "2" stamped a few places on the porthole. The glass viewing space measures 5" in diameter. The porthole is opened by the brass handle on the gear and turning it to line up the gear teeth to open. Excellent condition.
Shipping is included in the price.