One Bronze Antique Porthole in great condition. Marked ABW and A2900 A3192Two swing levers that hold the porthole tightly closed and an arm that holds it open. The overall size is approximately 17" x 10"The flange for the opening is approximately 14-1/2" x 7-1/2" (this is the size opening you need to mount the porthole). The flange is 3/8"