Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 1-1/2" Hose, 1-1/2" Max Hull (50-18631)
Free returns on all eligible orders
You have 30 days to request a return. All sale items are final sale.
The Seachoice Mega-Flow Dripless Thru-Hull Fitting is a polished 316 stainless steel through-hull designed for gray-water discharge applications on fiberglass and aluminum hulls up to 1-1/2 in. thick. Its thin-wall body maximizes water flow while the integrated drip collar on the face prevents unsightly hull streaking. A machined inner bore reduces the chance of debris accumulation, and a watertight gasket is included for a secure, leak-free installation. This is the 1-1/2 in. hose version — the largest in the Mega-Flow Dripless series — suited for high-volume drain applications on larger vessels.
Best Use Case: Ideal for large cockpit drains, bilge discharge, and high-volume gray-water through-hull applications on mid-to-large vessels requiring a 1-1/2 in. hose connection. The larger flange (2-3/8 in.) provides a secure, watertight mount on thicker hull sections. Not recommended for raw-water intake or fuel applications.
- 316 polished stainless steel — superior saltwater corrosion resistance
- Drip collar prevents hull streaking
- Thin-wall construction maximizes water flow
- Machined inner bore reduces debris accumulation
- Fits 1-1/2 in. hose ID
- Maximum hull thickness: 1-1/2 in.
- Flange diameter: 2-3/8 in.
- Watertight gasket included
- Part No. 50-18631
Parts Desk Insights: This is the largest hose size in the Mega-Flow Dripless series and is commonly used for main cockpit scuppers on cruising sailboats and larger powerboats. If your application requires a smaller hose barb, the full series is available: 1-1/8" Hose (50-18621), 1" Hose (50-18611), 3/4" Hose (50-18601), and 5/8" Hose (50-18591). Always verify hose ID and hull thickness before ordering. Pair with a compatible seacock or ball valve for a complete through-hull assembly.
Shipping information
In-stock and OEM parts: ship same or next business day.
Locally warehoused items: ship within 3–4 business days.
Special-order items: timeline confirmed after order.
Returns & warranty
Returns & Satisfaction Guarantee
We stand firmly behind the quality of every product we sell. Your confidence matters to us — and we back it with a straightforward 30-Day Satisfaction Guarantee.
If you are not fully satisfied, you may request a return within 30 days of delivery. All returns must receive pre-approval prior to being sent back. Unauthorized returns will not be accepted.
To qualify for a return:
Item must be in new, unused condition
Product must be in its original packaging
All parts, components, hardware, manuals, and accessories must be included
Packaging must be undamaged and suitable for resale
Important:
Electronics are strictly inspected. No returns on open-box electronics. Exceptions may apply only with prior written approval. Any electronic unit that has been installed, powered, activated, or altered may not be eligible for return.
We are serious about product integrity — and equally serious about taking care of our customers. If there is ever a product issue, contact us immediately so we can make it right.
For return authorization, please contact our support team before shipping anything back.