We have this wonderful original cast aluminum porthole that weighs 9 pounds.  The outside edge of the frame measures 26 x 10 1/2 inches. The glass measures 22 x 6 1/4 inches. On the back, the raised flange measures about 23 1/2 x 7 1/2 inches x 1 inch deep. The three latches move freely and the arm that holds the window open works; the glass is original and has minor surface scratches.