Feature:1. Parameter: The window size is 495x495mm, the installation cut out size is 425x435mm, and the installation thickness is 23‑55mm, or any thickness.2. Stronger: Sturdy ABS molded design and thick tempered glass for maximum durability. With anti aging, impact and corrosion resistant features.3. Waterproof Sealed: Designed with durable watertight rubber seal, effectively prevent rainwater from entering, no air leakage, good sealing.4. Opening Angle: Square design, with switch lock handle and support rod, 0‑160 degrees adjusted, convenient to enjoy the scenery along the way.5. Application: The windows are designed with tinted tempered glass with anti ultraviolet and anti aging effects, suitable for boat, yacht, ship, and RV.Specification:Item Type: Boat Portlight Hatch WindowMaterial: Aluminum alloy + stainless steel + rubber + ABS + tempered glass.Window Dimensions: Approx. 495x495mm/19.49x19.49inInstallation Cut Out Size: Approx. 425x435mm/16.73x17.13inSuitable Thickness: 23-55mm/0.91-2.17in, or any thicknessApplication: Applicable for Boat, Yacht, Nautical, RVPackage List:1 xBoat Portlight Hatch Window1 x Mounting FrameNote:Installation is slightly more difficult, it is recommended to find a professional engineer to assist in installation