General description - The Round Opening Porthole is designed for boats, yachts, RVs, and industrial vehicles. It features a solid ABS molded design that is anti-aging, anti-corrosion, and ultraviolet resistant, ensuring durability and longevity. Technical specifications Thickness of glass: 4mm (0.15 inch) Overall outside diameter: 10.4 inch / 265 mm Opening diameter with open window: approx. 7 3/4 inch / 197 mm Material: Tempered glass and 316 stainless steel fittings Compatibility and accessories 1 Piece Porthole Installation Easy to install with pre-drilled countersunk mounting holes (screws not included) Both fittings can be loosened to allow you to open the porthole Other information Corrosion-free synthetic fittings and waterproof, durable rubber seals Image: