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Sea-Dog Line 521130 Exhaust Thru-Hull Fitting - Cast 316 Stainless Steel

Manufacturer

Sea-Dog Line

<p>For over a century, Sea-Dog Line has stood as a cornerstone of the marine hardware industry, delivering innovative solutions that meet the demanding needs of recreational and commercial boaters. Founded in the early 1920s by entrepreneur Hans "Action" Broson Sneve, the company began with a unique sales approach—showcasing marine hardware aboard a 55-foot cruiser that sailed from Alaska to Mexico. This hands-on philosophy continues to shape Sea-Dog's commitment to producing hardware that performs reliably in the harshest saltwater environments.</p><h3>Industry-Leading Marine Hardware Manufacturing</h3><p>Based in Everett, Washington, Sea-Dog Corporation operates a 75,000-square-foot warehouse stocking over 8 million parts and runs an injection molding facility with 16 machines producing more than 17 million components annually. The company's extensive product line spans anchoring systems, deck hardware, electrical components, plumbing fittings, and lighting solutions—all engineered with marine-grade materials like stainless steel, brass, and UV-resistant polymers. Sea-Dog's recognition as a multiple-time NMDA Supplier of the Year underscores the brand's excellence in both product quality and customer service, while their on-staff ABYC-certified marine technician provides invaluable installation and technical support.</p><h3>Premium Marine Components for Every Vessel</h3><p>Sea-Dog's <a href="/7549-sea-dog-line-windshield-washers-wipers-replacement-motors-201195">windshield washers, wipers, and replacement motors</a> deliver crystal-clear visibility during inclement weather, with both manual and electric options featuring corrosion-resistant stainless steel arms and UV-stable blades designed specifically for marine windshield applications. Their <a href="/7549-sea-dog-line-electric-horns-200351">electric horns</a> include the popular MaxBlast line, which passed rigorous 600-hour salt spray testing while meeting US Coast Guard COLREGS and ABYC standards for audible warning devices. For fuel and water system integrity, Sea-Dog's <a href="/7549-sea-dog-line-deck-fills-200307">deck fills</a> provide secure, leak-free access points constructed from durable stainless steel with snap-in designs that resist corrosion in saltwater environments.</p><p>When maneuvering in low-light conditions, Sea-Dog's <a href="/7549-sea-dog-line-docking-lights-200335">docking lights</a> offer bright LED illumination with minimal power draw, featuring injection-molded housings that withstand impacts and temperature extremes. Proper airflow is essential for preventing moisture buildup below deck, and Sea-Dog's <a href="/7549-sea-dog-line-hose-and-cowl-vents-200534">hose and cowl vents</a> deliver reliable ventilation with low-profile designs that include snap-in deck plates for bilge applications or dorade box compatibility for cabin use. Each product reflects Sea-Dog's century-long dedication to manufacturing hardware that recreational and professional mariners can trust, voyage after voyage.</p>

Part Number

521130
06/21/2036 2:08 PM
Sale Price

$119.64

In Stock (10+)

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Sea-Dog Line 521130 exhaust thru-hull fitting is engineered for reliable marine exhaust discharge applications. Constructed from corrosion-resistant cast 316 stainless steel, this fitting is built to withstand the harsh marine environment and provide long-lasting performance.

Key Features:

  • Cast 316 stainless steel construction for superior corrosion resistance
  • Includes stainless steel flap valve with integrated rubber seal
  • Prevents backflow of water into exhaust system
  • Flapper design minimizes water intrusion when engine is off
  • Designed for through-hull installation on powerboats and sailboats
  • Suitable for diesel and gasoline engine exhaust systems

This thru-hull exhaust fitting provides a professional solution for routing engine exhaust through the hull while preventing water from entering the system. The rubber-sealed flap creates a positive seal when closed, protecting your engine and exhaust components from saltwater damage.

Products specifications

Hose Fitting Size

3"

Length

5-7/8"

ok so far

Efficient checkout.

Very smooth

good price, prompt delivery. no complaints.

Very good price on my purchase and free shipping!

helped me find the exact one i needed

goodprice

Easy to find parts and good prices. I hope shipping is just as fast and easy.

I don't typically review online stores, but Autoplicity was awesome! Shipped ridiculously quickly and my H&R springs were at my house two days after I ordered. Awesome, and for a great price. Thanks guys

cool

no place to put discount shipping code

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