SEAFLO Thru Hull Fitting Plastic Drain Overflow Connector - Saltwater

In this review of the SEAFLO Thru Hull Fitting the bottom line is simple: it is a practical, corrosion-free option for above-waterline drain and bilge outlets on small boats, kayaks, and RVs. Built from injection-molded polypropylene and offered in a 10-pack, this fitting is aimed at boaters who need a reliable overflow or bilge port that resists UV, saltwater, oil and fuel. The reviewer found the fitting easy to install and well suited to non-submerged plumbing where compliance with ABYC standards and long-term resistance to metal corrosion matter most.

Key Features

• Marine-grade construction: The polypropylene body resists corrosion from saltwater and eliminates metal corrosion risks in exposed deck fittings.
• ABYC compliance: Meets small craft safety guidelines for non-submerged through hull and deck outlet installations, giving confidence in safety and compatibility.
• Easy installation: A broad mounting flange and precision-molded threads allow secure, vibration-resistant sealing with common marine tools.
• UV and chemical resistance: Injection-molded polypropylene is durable against UV exposure, oil and fuel, extending useful life in harsh marine environments.
• Pack quantity: Supplied as a 10-pack which is useful when outfitting multiple drain points, spares, or for small fleet maintenance.

Who It's For

The SEAFLO Thru Hull Fitting is best for recreational boat owners, DIY installers, and fleet maintainers who need an above-waterline overflow or bilge port that resists corrosion and meets ABYC guidance. It is ideal for livewells, bilge outlets and overflow drains where metal fittings would be a liability and multiple identical parts are useful.

Those who should look elsewhere include owners who require submerged through-hull seacocks or custom metal fittings for maximum structural strength; this polypropylene connector is designed for non-submerged applications and above-waterline use only. Also check sizing carefully if your hull openings are nonstandard, since a few customers received the wrong size.

Pros & Cons

Pros

• Corrosion-resistant polypropylene eliminates metal rust and performs well in saltwater environments.
• Easy to install with a wide flange and molded threads that provide a secure seal without adhesives.
• Good value provided as a 10-pack for multiple fittings or spares.
• Complies with ABYC guidelines for small craft, suitable for safe above-waterline plumbing.

Cons

• Some buyers report receiving the wrong size, so verify dimensions before installation.
• Not intended for submerged through-hull service where a metal seacock or reinforced fitting is required.

Specifications

Our Verdict

The SEAFLO Thru Hull Fitting is a sensible, cost-effective choice for anyone fitting multiple overflow drains or bilge outlets above the waterline. Its polypropylene construction and ABYC compliance make it a durable, low-maintenance option that avoids metal corrosion, and the 10-pack format is convenient for builders and maintainers. Verify size carefully before ordering, but for compliant, non-submerged applications this fitting offers solid value and ease of installation.

Frequently Asked Questions

Is this fitting suitable for submerged through-hull use?
No. This fitting is designed for above-waterline overflow and bilge outlets and is not intended to replace a submerged seacock or structural through-hull.

What material is the fitting made from?
The fitting is injection-molded polypropylene, chosen for UV, saltwater, oil and fuel resistance and to avoid metal corrosion.

Does it meet marine safety standards?
Yes. The fitting is described as meeting ABYC guidelines for small craft fittings for non-submerged applications.