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Sea-Dog Line 520831 90° Thru-Hull Fitting with Stainless Steel Cap

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

520831
06/13/2036 6:53 AM
Sale Price

$18.50

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sea-Dog Line 520831 is a 90-degree thru-hull fitting designed to allow controlled water passage in or out of a vessel above the waterline. This marine-grade fitting is ideal for drainage applications, bilge pump outlets, livewell systems, and other onboard plumbing needs.

Key Features:

  • Injection-molded polypropylene body for excellent corrosion resistance and durability
  • 304 stainless steel cap provides superior strength and marine-grade corrosion protection
  • 90-degree angle configuration for efficient hose routing in tight spaces
  • Designed for use with marine hose for above-waterline drainage applications
  • Threaded design allows secure installation through hull or bulkhead

Specifications:

  • Dimension A (Overall Height): 1-7/8"
  • Dimension B (Thread Length): 7/8"
  • Dimension C (Cap Diameter): 1-13/16"
  • Dimension D (Base Flange): 3-7/16"
  • Dimension E (Outlet Length): 1-15/16"
  • Dimension F (Hose Barb): 3/4" for standard marine hose connection

This fitting combines the chemical resistance and lightweight properties of polypropylene with the strength and corrosion resistance of stainless steel, making it an excellent choice for marine drainage systems, bait tank plumbing, and other wet applications on boats, yachts, and personal watercraft.

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great and easy

great price and availability

Easy and very competitive pricing

It was fast service

Good prices and the tires were fresh. No complaints or issues.

Easy to purchase, received my product rather quickly and on time.

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