This salvaged brass porthole window has a 10 inch brass frame. The original glass is 6 3/4 inches in diameter. The opening window frame is 7 3/4 inches in diameter and opens and closes freely. The two wing nut closures work freely to lock the window closed. The flange ring on the back of the frame is 7 1/4 inches wide and extends out from the back of the main frame by 3 inches. This salvaged brass porthole window weighs almost 12 pounds.