Vintage Bronze/Brass Porthole/Deck Plate/ Hatch Cover Nautical Ship maritime

I AM NOT SURE EXACTLY WHAT THIS IS AS THERE IS NO GLASS. IT LOOKS LIKE A PORTHOLE BUT HAVE SEEN THEM CALLED A HATCH COVER OR DECK PLATE. THE OPENING IS 7", INCLUDING FRAME IT IS 9" AND 1 1/4" DEEP. ALL 3 OF THE DOGS WORK GREAT. IT LOOKS LIKE THERE WAS SOME SOLDER THAT FILLED THE MOUNTING HOLES AT ONE TIME FOR SOME REASON THAT SOMEONE GRINDED OFF AND PART OF THE COVER HAD BEEN SOMEWHAT POLISHED. I BELIEVE THE MATERIAL IS BRONZE. WEIGHT IS JUST OVER 5 LBS. PLEASE ASK IF YOU HAVE ANY QUESTIONS AND THANKS FOR LOOKING.