Boat, RV, or caravan owner? This XTevu deck filler is a solid piece of marine-grade hardware for your fuel tank. It's made from high-quality 316 stainless steel, which is the good stuff – it's highly resistant to rust and corrosion, perfect for salty marine environments or long-term outdoor use. The hole size is 50mm (2 inches), designed to fit a standard 50mm diameter fuel hose. The cap has a simple, keyless design: just lift the little tab and turn to open or close. It seals tightly with an included O-ring to prevent leaks and fumes. A super handy feature is the stainless steel retaining chain, so you won't ever lose the cap overboard or in a field. The surface is mirror polished, so it looks sleek and is easy to wipe clean. Ideal for diesel or gas fill points on yachts, boats, campervans, caravans, RVs, trucks, or tractors. An affordable upgrade or replacement that's built to last.