Marine Thru‑Hull Fittings in Bronze, Stainless & Marelon

This collection of marine thru‑hull fittings provides durable, corrosion‑resistant solutions for raw‑water intakes, cockpit drains, bilge outlets, livewell systems, and general marine plumbing. Featuring a wide selection from trusted brands like GROCO, Perko, Forespar (Marelon), and Johnson Pump, this category includes bronze, stainless steel, and Marelon composite fittings in multiple sizes and configurations.

Choose from straight, 90‑degree, long‑neck, flush‑mount, and scupper‑style thru‑hulls designed for both above‑ and below‑waterline installations. Options include NPSM threaded fittings, hose‑barb combinations, flanged models, and UV‑stable Marelon fittings ideal for saltwater environments. Bronze models offer unmatched strength for seacock installations, while stainless steel provides a polished, modern finish for topside and transom applications.

Whether upgrading a raw‑water intake, replacing a corroded fitting, or outfitting a new plumbing system, these thru‑hulls deliver the reliability, flow performance, and long‑term durability required for safe marine operation.

Key Features of Our Marine Thru‑Hull Fittings

• Bronze, stainless steel, and Marelon composite construction
• Straight, 90‑degree, long‑neck, and scupper configurations
• NPSM threaded and hose‑barb combinations available
• Suitable for raw‑water intakes, drains, and plumbing systems
• UV‑resistant Marelon options for corrosion‑free performance
• Heavy‑duty bronze models ideal for seacock installations
• Polished stainless steel fittings for topside applications
• Wide range of diameters for custom plumbing layouts
• Compatible with GROCO, Perko, Forespar, and Johnson Pump systems
• Designed for long‑term durability in harsh marine environments

FAQs

1. What material is best for marine thru‑hull fittings?

Bronze is preferred for below‑waterline seacock installations, stainless steel is ideal for topside and transom use, and Marelon offers corrosion‑proof performance in both fresh and saltwater.

2. How do I choose the correct size thru‑hull fitting?

Match the fitting to your hose ID and ensure the thread type (NPSM) matches your seacock or valve. Always verify clearance and hull thickness before installation.

3. Can Marelon thru‑hull fittings be used below the waterline?

Yes — Forespar Marelon fittings are engineered for below‑waterline use, offering UV stability, corrosion resistance, and compliance with marine safety standards.