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Groco BB-2 Flanged Seacock Backing Block 1/2 Inch PVC Foam

Manufacturer

Groco

<p>For more than a century, Groco has stood as a pillar of American marine manufacturing excellence. Founded in 1918 by inventor Angus Roy Gross Sr. in a Baltimore basement, Gross Mechanical Laboratories—now known simply as Groco—began with an innovative spirit that led to patents ranging from blow torches to automobile taillights. By the late 1920s, the company shifted its focus entirely to the marine industry, where it has remained a trusted name for boaters and marine professionals who demand precision-engineered underwater hardware.</p><p>Headquartered in Stevensville, Maryland, Groco has built its reputation on two unwavering principles: innovative design and sound construction. Every product that bears the Groco name is crafted from premium materials like C84400 bronze and marine-grade stainless steel, engineered to withstand the harsh realities of saltwater environments. From recreational vessels to commercial workboats, Groco hardware delivers the reliability that keeps critical systems operating when it matters most.</p><h3>Essential Marine Plumbing Solutions</h3><p>At the heart of Groco's product lineup are their industry-leading <a href="/7373-groco-sea-strainers-200906">sea strainers</a>, which protect engines and pumps from debris that can cause catastrophic damage. These raw water strainers feature clear sight glasses for easy inspection and robust baskets that trap grass, kelp, and other materials before they reach sensitive equipment. Groco's innovative self-cleaning strainer models eliminate the need for system shutdown during cleaning cycles, keeping vessels operational longer.</p><p>Water flow control begins at the hull, and Groco's <a href="/7373-groco-seacocks-200913">seacocks</a> set the standard for below-waterline safety. Unlike generic valves, genuine Groco seacocks feature flanged bases that distribute stress across the hull structure, along with drain plugs for winterization and grease fittings for maintenance. These critical shut-off points give boaters confidence that their vessel's integrity is protected by hardware engineered specifically for marine applications.</p><p>Completing the underwater plumbing system, Groco manufactures precision <a href="/7373-groco-thru-hull-fittings-201065">thru-hull fittings</a> designed to resist galvanic corrosion while providing secure connections for intake and discharge lines. Their <a href="/7373-groco-scoop-round-strainers-200899">scoop and round strainers</a> serve as the first line of defense, removing larger debris at the point of water entry. For applications requiring precise flow control, Groco's <a href="/7373-groco-ball-valves-200130">ball valves</a> deliver full-port flow and quarter-turn operation with chrome-plated bronze balls and glass-reinforced PTFE seats.</p><h3>Engineering Excellence You Can Trust</h3><p>What separates Groco from competitors is their commitment to continuous improvement through advanced manufacturing. The company has evolved from manual machining to state-of-the-art CNC technology, ensuring every component meets exacting tolerances. This dedication to quality means that when you install Groco hardware, you're choosing products that have been refined through decades of real-world marine experience and are built to perform reliably for years to come.</p>

Part Number

BB-2
06/01/2036 2:38 AM
Sale Price

$47.06

3 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Groco BB-2 backing block improves flanged seacock installations by providing a solid mounting surface between the valve flange and the hull. This marine-grade backing block ensures secure, leak-free through-hull connections.

Key Features:

  • 1/2 inch thickness provides rigidity for secure installation while remaining flexible enough to conform to minor hull curvature
  • Each size fits multiple seacock sizes for versatile applications
  • Press-fit threaded inserts install into the hull side of the backing block, aligning with seacock flange bolt holes
  • Made from environmentally friendly PVC foam specially formulated for marine environments
  • Will not swell, rot, or absorb moisture like traditional wood backing blocks

This backing block distributes fastener loads across a wider area of the hull, preventing stress cracks and ensuring a watertight seal. Ideal for new installations or replacing deteriorated wood backing blocks on existing through-hull fittings.

Products specifications

Fits with

1-1/4" & 1-1/2" Seacocks

Size

5.38" Dia. w/ 5/16"-18 Threads

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Found what I needed for a good price. They Forgot to send my shipping info but my order still arrived on time so it was no big deal.

Thank you for the great prices

I ordered a Thule 872XT 44" Fairing from them because they had the best deal on a new one and their shipping was fair. I live on Long Island N.Y. and got my order in 2 days! I did not expect the fast shipping but i am very thankful for it! I received an email when i paid, when my order shipped and then when my order was delivered to my door. I never heard of this online vendor until i was searching for the Thule but they had very positive reviews so i had little to lose. I will look to them first for future needs. A+!

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Well, I'll start with saying this...I wanted a specific product from COBB tuning that they sell. It was priced lower than any other company so I bought it. This happened on the 22nd, I ended up calling them almost a week later to request tracking info. They were very friendly when they notified me it wouldn't be able to ship out till the 3rd of feb. For a 2 lb item I thought this was pretty slow. They apologized for COBB holding the order up. Its now the 7th, should get my item today!! Overall its a good company with friendly employees, Shipping time is lacking but a trade off for the lowest price. I would refer a friend for price and also mention shipping time expectations. I do believe there's something to be said for quality customer service and low prices...It's becoming harder and harder to find companies that posses such qualities. Honestly, if they had a faster shipping method I would give them a perfect rating.<br>

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