Attwood White Plastic Thru-Hull Fitting - 1-1/8" Inner Diameter

The Attwood White Plastic Thru-Hull Fitting with 1-1/8" inner diameter is an essential through-hull component for any boat owner managing water intake, drainage, or ventilation systems. Whether you're running a raw-water cooling loop, bilge pump discharge, or cabin ventilation line, this fitting provides a reliable seal where hoses pass through the hull. After decades on the water, reliable thru-hulls aren't a luxury—they're the difference between a dry bilge and a long afternoon with a submersible pump.

Constructed from durable thermoplastic material, this fitting eliminates the electrolysis problems that plague traditional bronze thru-hulls in saltwater environments. The white plastic body resists corrosion, galvanic action, and salt spray degradation—critical advantages in marine applications where metal fittings can develop pinhole leaks or stress fractures over time. The 1-1/8" inner diameter accommodates standard marine hose sizes, ensuring compatibility with common bilge, cooling, and drainage systems found on center consoles, cabin cruisers, and commercial vessels.

This thru-hull fitting is ideal for boat owners performing routine maintenance, emergency repairs, or complete system upgrades. Installation requires access to both the interior and exterior hull surface, so plan your work during haul-out or dry-dock periods. Pair this fitting with appropriate seacocks or ball valves to maintain full control over water flow, and always use marine-grade sealant around the hull penetration to prevent leaks. For fiberglass hulls, wood vessels, or aluminum transoms, verify mounting hole dimensions and use backing plates to distribute fastener load and prevent hull cracking.