This diver recovered one dog brass porthole window with original paint has a 9 inch frame. The original glass measures 5 1/4 inches in diameter. The opening window frame is 6 1/2 inches in diameter and opens and closes freely. The wing nut closure on this one dog brass porthole window moves freely to lock the window closed. The flange ring on the back is 6 inches in diameter and extends back from the mounting ring by 2 inches. This porthole weighs 6 3/4 pounds.