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Groco BB-1 Backing Block for Flanged Seacock Installation

Manufacturer

Groco

<h3>About Groco: A Century of Marine Innovation</h3><p>Few names in the marine hardware industry carry the weight of experience and craftsmanship that <strong>Groco</strong> does. Short for Gross Mechanical Laboratories, Inc., Groco was founded in 1918 by Angus Roy Gross Sr. — a tinkerer and innovator who started the company in the basement of a Baltimore row house. From those humble beginnings, Angus and his personally trained team built a reputation rooted in precision engineering and an uncompromising commitment to quality that continues to define the brand more than a century later.</p><p>Headquartered in Stevensville, Maryland, Groco has long been the go-to source for boaters and marine professionals who demand components that perform reliably in the demanding saltwater environment. Angus's inventive spirit led to numerous patents across a surprisingly diverse range of products — from carbonating faucets to automotive tail lights — but it was marine hardware where Groco truly found its calling. That same drive to improve and redesign is baked into every product Groco produces today.</p><h3>What Groco Makes</h3><p>Groco's catalog spans a wide range of below-the-waterline and through-hull marine hardware, with two standout categories that have earned particular loyalty among boat owners and shipbuilders alike.</p><p>One of Groco's most trusted product lines is their <a href="/7373-groco-sea-strainers-200906">sea strainers</a>. Designed to protect raw water cooling systems, pumps, and engines from debris and fouling, Groco sea strainers are engineered to handle the rigors of continuous marine use. Whether you're outfitting a small inboard cruiser or a large commercial vessel, the right strainer is an essential safeguard — and Groco's lineup offers solutions across a wide range of flow rates and installation configurations.</p><p>Equally important to any vessel's integrity are reliable <a href="/7373-groco-thru-hull-fittings-201065">thru-hull fittings</a>. These critical components form the sealed connections between a boat's hull and its plumbing systems, and a failure here can have serious consequences. Groco's thru-hull fittings are manufactured to exacting tolerances, using materials suited for long-term exposure to seawater. Boaters and marine builders have trusted Groco's fittings for generations precisely because the stakes are too high to compromise.</p><h3>Why Boaters Choose Groco</h3><ul style="list-style:disc"><li><strong>Over 100 years of marine expertise</strong> — founded in 1918, with deep roots in innovative engineering</li><li><strong>Made in the USA</strong> — headquartered in Stevensville, Maryland, with a tradition of American craftsmanship</li><li><strong>Engineered for longevity</strong> — products are built to withstand the corrosive, high-stress marine environment</li><li><strong>Broad product range</strong> — with nearly 400 products across multiple marine hardware categories</li><li><strong>Trusted by professionals</strong> — used by boat builders, marine mechanics, and serious boaters worldwide</li></ul><p>Whether you're replacing aging hardware on a classic cruiser or speccing out a new build, Groco's marine hardware represents a standard that serious mariners have relied on for over a century.</p>

Part Number

BB-1
09/12/2036 6:48 AM
Sale Price

$37.12

2 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Groco BB-1 backing block is designed to improve flanged seacock installations by providing a stable, moisture-resistant interface between the valve flange and the hull. This marine-grade backing block ensures a secure, long-lasting installation that conforms to minor hull irregularities.

Key Features:

  • Universal fit design - each size accommodates multiple seacock sizes
  • 1/2" thickness provides optimal rigidity for secure mounting while remaining flexible enough to conform to minor hull curvature
  • Threaded inserts press into the hull side of the backing block, aligning with seacock flange mounting holes
  • Non-absorbent material will not swell or retain moisture in marine environments
  • Constructed from environmentally friendly PVC foam specially formulated for marine applications

This backing block distributes load evenly across the hull surface and provides a professional foundation for through-hull seacock installations. The marine-grade PVC foam construction ensures durability and resistance to the harsh marine environment.

Products specifications

Fits with

3/4" & 1" Seacocks

Size

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

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Very easy to navigate web site. Received my order in excellent condition in a timely manner. Recommend Autoplicity as a company with which to conduct business.

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