Marine Portlight Window Internal Opening UV Resistant Waterproof Oval Shape Boat Portlight Hatch Window for Yacht Item Type: Marine Portlight Window Material: Aluminum Alloy, ABS, Acrylic Porthole Size: Approx. 470x210mm / 18.5x8.3in Installation Opening Size: Approx. 405x150mm / 15.9x5.9in Suitable For Installation Thickness: 10-40mm /0.4-1.6in Wall Thickness Application: Transparent Window Can Increase The Brightness Of The Cabin, Can Be Used For Ventilation Window, Completely Sealed And Waterproof, With Locking Fixed Handle Suitable: Good For Boat, Yacht, Ship, And RV Installation Instructions: The Window Is Inward Opening Type, The Fixed Frame Is Installed Outside The Cabin, The Glass Surface Is The Inside Surface Of The Cabin