Sea-Dog Deck Fill Cap with Chain | 351391-1

If you own a boat long enough, a deck fill cap goes missing. Somebody fuels up, sets the cap on the gunwale, and a wake does the rest. Or the old one corrodes until it won't turn. This is the genuine Sea-Dog replacement cap for that exact moment, so you're not left with an open fill on the deck.

It's machined from 316 stainless steel, which is the grade that actually belongs on saltwater boats. 316 holds up to salt spray and standing water far better than the cheaper 304 stainless you'll find on bargain hardware, and it keeps that bright finish instead of tea-staining after a season. On a deck fill, a fitting that's handled wet and sits exposed to the weather all day, that corrosion resistance is the whole point.

One thing to be clear about: this is the cap only. It's the replacement top for a 2-inch hose deck fill, not the complete fill assembly. If your deck fill body is cracked or the flange is shot, you'll want the full unit instead. But if the base is fine and you just need the cap, this drops right in. It fits the Sea-Dog deck fills in the 351350 through 351353 range.

Deck fills like these handle fuel, water, or waste depending on how your boat is plumbed, and the cap is what keeps the weather and spray out between fills. A missing or leaking cap lets rain and washdown water work into the line, which is exactly what you don't want in a fuel or fresh-water fill. Keeping a good stainless cap on it is cheap insurance.

The attachment chain comes with it, and it's worth using. Thread it to the anchor point on your fill so the cap stays tethered while you're fueling or filling water. That's how you avoid buying this part twice. Installation is straightforward, no special tools, and you're back to a clean, sealed deck fill in a couple of minutes.