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Seacocks & Thru-Hulls

Marine Plumbing

Seacocks, Thru-Hulls, Strainers & Below-Waterline Fittings

Shop marine seacocks, thru-hull fittings, raw-water strainers, valves, guards, fittings, and installation supplies for intake, discharge, drainage, and cooling systems.

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SeacocksShutoff valves for intake and discharge points below the waterline. Thru-Hull FittingsBronze, stainless, nylon, straight, angled, and mushroom-head fittings. Raw-Water StrainersProtect engines, pumps, generators, and air conditioning systems. Valves & FittingsAdapters, elbows, hose tails, drains, and plumbing connection parts. Sealants & BeddingMarine sealants for bedding hardware and fittings. Guards & ProtectionDrip guards and small protection pieces around hull fittings.

Below-Waterline Parts Need Careful Matching

Confirm hose inside diameter, thread type, material compatibility, bonding requirements, valve access, and whether the fitting is above or below the waterline. When in doubt, match the existing fitting and ask for help before replacing critical hull plumbing.

Filters

Attwood Thru Hull Stainless Steel 3/4" For Hose

Attwood Thru Hull Stainless Steel 3/4" For Hose

$77.59 - $77.59
$77.59
$77.59 - $77.59
$77.59
Item locally warehoused

Cast from 316 stainless steel. A channel under the flange holds a bead of sealant. All models have wrench flats or an end notch. Designed for insta...

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$77.59 - $77.59
$77.59
$77.59 - $77.59
$77.59
Attwood Thru Hull Stainless Steel 1-1/4" For Hose, Short

Attwood Thru Hull Stainless Steel 1-1/4" For Hose, Short

$122.79 - $122.79
$122.79
$122.79 - $122.79
$122.79
Item locally warehoused

Cast from 316 stainless steel. A channel under the flange holds a bead of sealant. All models have wrench flats or an end notch. Designed for insta...

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$122.79 - $122.79
$122.79
$122.79 - $122.79
$122.79
Attwood Thru Hull Stainless Steel 1-1/8" For Hose, Short

Attwood Thru Hull Stainless Steel 1-1/8" For Hose, Short

$105.59 - $105.59
$105.59
$105.59 - $105.59
$105.59
Item locally warehoused

Cast from 316 stainless steel. A channel under the flange holds a bead of sealant. All models have wrench flats or an end notch. Designed for insta...

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$105.59 - $105.59
$105.59
$105.59 - $105.59
$105.59
Attwood Thru Hull Stainless Steel 3/4" For Hose, Short

Attwood Thru Hull Stainless Steel 3/4" For Hose, Short

$74.19 - $74.19
$74.19
$74.19 - $74.19
$74.19
Item locally warehoused

Cast from 316 stainless steel. A channel under the flange holds a bead of sealant. All models have wrench flats or an end notch. Designed for insta...

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$74.19 - $74.19
$74.19
$74.19 - $74.19
$74.19
Groco ARG1000S Bronze Strainer With #304 SS Basket

Groco ARG-1000-S Bronze Raw-Water Strainer | 1" Hose | #304 SS Basket

$694.69 - $694.69
$694.69
$694.69 - $694.69
$694.69
Item locally warehoused

Groco ARG-1000-S Bronze Raw-Water Strainer — 1" Hose | #304 SS BasketKeep your raw-water cooling and washdown systems running clean with this heavy...

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$694.69 - $694.69
$694.69
$694.69 - $694.69
$694.69
Groco ARG750S Bronze Strainer With #304 SS Basket

Groco ARG-750-S Bronze Raw-Water Strainer | 3/4" Hose | #304 SS Basket

$477.59 - $477.59
$477.59
$477.59 - $477.59
$477.59
Item locally warehoused

Groco ARG-750-S Bronze Raw-Water Strainer — 3/4" Hose | #304 SS BasketProtect your raw-water cooling and washdown systems from debris with this hea...

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$477.59 - $477.59
$477.59
$477.59 - $477.59
$477.59
Groco ARG500S Bronze Strainer With #304 SS Basket

GROCO ARG-500S Bronze Raw-Water Strainer — 1/2" Hose, #304 SS Basket (34-ARG500S)

$465.99 - $465.99
$465.99
$465.99 - $465.99
$465.99
Item locally warehoused

The GROCO ARG-500S is a compact bronze raw-water strainer designed for 1/2 in. pipe or hose connections. It brings the same proven ARG-series const...

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$465.99 - $465.99
$465.99
$465.99 - $465.99
$465.99
Groco ARG2500S Bronze Strainer With #304 SS Basket

GROCO ARG-2500S Bronze Raw-Water Strainer — 2-1/2" Hose, #304 SS Basket (34-ARG2500S)

$1,347.59 - $1,347.59
$1,347.59
$1,347.59 - $1,347.59
$1,347.59
Item locally warehoused

The GROCO ARG-2500S is a large-capacity bronze raw-water strainer designed for 2-1/2 in. pipe or hose connections. Built for high-volume seawater i...

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$1,347.59 - $1,347.59
$1,347.59
$1,347.59 - $1,347.59
$1,347.59
Groco ARG2000S Bronze Strainer With #304 SS Basket

GROCO ARG-2000S Bronze Raw-Water Strainer — 2" Hose, #304 SS Basket (34-ARG2000S)

$1,157.59 - $1,157.59
$1,157.59
$1,157.59 - $1,157.59
$1,157.59
Item locally warehoused

The GROCO ARG-2000S is a heavy-duty bronze raw-water strainer built for high-volume seawater intake applications on larger vessels. Designed for 2 ...

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$1,157.59 - $1,157.59
$1,157.59
$1,157.59 - $1,157.59
$1,157.59
Groco ARG1500S Bronze Strainer With #304 SS Basket

GROCO ARG-1500S Bronze Raw-Water Strainer — 1-1/2" Hose, #304 SS Basket (34-ARG1500S)

$1,087.49 - $1,087.49
$1,087.49
$1,087.49 - $1,087.49
$1,087.49
Item locally warehoused

The GROCO ARG-1500S is a heavy-duty bronze raw-water strainer designed for inboard engine cooling systems, generator cooling, and other high-flow s...

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$1,087.49 - $1,087.49
$1,087.49
$1,087.49 - $1,087.49
$1,087.49
Groco ARG1250S Bronze Strainer With #304 SS Basket

Groco ARG1250S Bronze Strainer With #304 SS Basket

$720.39 - $720.39
$720.39
$720.39 - $720.39
$720.39
Item locally warehoused

Standard single strainers. No tie rods or leaks under pressure or vacuum. Quick and easy mounting system allowing removal of strainer without tools...

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$720.39 - $720.39
$720.39
$720.39 - $720.39
$720.39
Seachoice Mega-Flow Dripless Thru Hull Fitting, 316 Stainless Steel, Fits 1-1/2 In. Hose, 1-1/2 In. Max. Hull

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 1-1/2" Hose, 1-1/2" Max Hull (50-18631)

$72.49 - $72.49
$72.49
$72.49 - $72.49
$72.49
Item locally warehoused

The Seachoice Mega-Flow Dripless Thru-Hull Fitting is a polished 316 stainless steel through-hull designed for gray-water discharge applications on...

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$72.49 - $72.49
$72.49
$72.49 - $72.49
$72.49
Seachoice Mega-Flow Dripless Thru Hull Fitting, 316 Stainless Steel, Fits 1-1/8 in. Hose, 1-1/2 in. Max. Hull

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 1-1/8" Hose, 1-1/2" Max Hull (50-18621)

$62.34 - $62.34
$62.34
$62.34 - $62.34
$62.34
Item locally warehoused

The Seachoice Mega-Flow Dripless Thru-Hull Fitting is a polished 316 stainless steel through-hull designed for gray-water discharge applications on...

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$62.34 - $62.34
$62.34
$62.34 - $62.34
$62.34
Seachoice Mega-Flow Dripless Thru Hull Fitting, 316 Stainless Steel, Fits 1 in. Hose, 1-1/2 in. Max. Hull

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 1" Hose, 1-1/2" Max Hull (50-18611)

$65.24 - $65.24
$65.24
$65.24 - $65.24
$65.24
Item locally warehoused

The Seachoice Mega-Flow Dripless Thru-Hull Fitting is a polished 316 stainless steel through-hull designed for gray-water discharge applications on...

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$65.24 - $65.24
$65.24
$65.24 - $65.24
$65.24
Seachoice Mega-Flow Dripless Thru Hull Fitting, 316 Stainless Steel, Fits 3/4 in. Hose, 1-1/2 in. Max. Hull

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 3/4" Hose, 1-1/2" Max Hull (50-18601)

$65.24 - $65.24
$65.24
$65.24 - $65.24
$65.24
Item locally warehoused

The Seachoice Mega-Flow Dripless Thru-Hull Fitting is a polished 316 stainless steel through-hull designed for gray-water discharge applications on...

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$65.24 - $65.24
$65.24
$65.24 - $65.24
$65.24
Seachoice Mega-Flow Dripless Thru Hull Fitting, 316 Stainless Steel, Fits 5/8 in. Hose, 1-1/2 in. Max. Hull

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 SS, 5/8" Hose, 1-1/2" Max Hull (50-18591)

$62.34 - $62.34
$62.34
$62.34 - $62.34
$62.34
Item locally warehoused

Seachoice Mega-Flow Dripless Thru-Hull Fitting — 316 Stainless Steel, 5/8" HoseA polished 316 stainless-steel thru-hull fitting engineered for maxi...

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$62.34 - $62.34
$62.34
$62.34 - $62.34
$62.34
Seachoice Thru-Hull Connector w/ Broad Flange, Fits 1 In. ID Hose, 1-1/4 In. Max Hull

Seachoice Thru-Hull Connector w/ Broad Flange, Fits 1 In. ID Hose, 1-1/4 In. Max Hull

$15.59 - $15.59
$15.59
$15.59 - $15.59
$15.59
Item locally warehoused

Upgrade your bilge plumbing with this Seachoice thru-hull connector featuring a broad flange for secure mounting. Designed for a 1-inch ID hose and...

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$15.59 - $15.59
$15.59
$15.59 - $15.59
$15.59
Seachoice Thru-Hull Connector w/ Broad Flange, Fits 3/4 In. ID Hose, 1-1/4 In. Max Hull

Seachoice Thru-Hull Connector w/ Broad Flange, Fits 3/4 In. ID Hose, 1-1/4 In. Max Hull

$8.39 - $8.39
$8.39
$8.39 - $8.39
$8.39
Item locally warehoused

Seachoice Thru-Hull Connectors with a broad flange are molded from durable, high-impact plastic to help you create a reliable above-waterline hose ...

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$8.39 - $8.39
$8.39
$8.39 - $8.39
$8.39
Seachoice Covered Thru-Hull Fitting w/ Stainless-Steel Flange, Fits 3/4 In. ID Hose

Seachoice Covered Thru-Hull Fitting w/ Stainless-Steel Flange, Fits 3/4 In. ID Hose

$21.37 - $21.37
$21.37
$21.37 - $21.37
$21.37
Item locally warehoused

Seachoice Covered Thru-Hull Fitting 50-18441 is designed for marine hose connections above the waterline, featuring a stainless-steel flange and a ...

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$21.37 - $21.37
$21.37
$21.37 - $21.37
$21.37
Groco ARG-506 Drain Wingnut and O-Ring For ARG Strainers Before 080101

GROCO ARG-506 Drain Wingnut & O-Ring — For ARG Strainers (Pre-August 2001)

$8.23 - $8.23
$8.23
$8.23 - $8.23
$8.23
Item locally warehoused

The GROCO ARG-506 is the OEM drain wingnut and O-ring replacement for GROCO ARG-series raw-water strainers manufactured before August 2001. If your...

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$8.23 - $8.23
$8.23
$8.23 - $8.23
$8.23

Attwood 5/8 in Composite Thru-Hull Fitting – ATT-68555-1

$16.50 - $16.50
$16.50
$16.50 - $16.50
$16.50
28 in stock

5/8 in Composite Thru-Hull Fitting for Marine PlumbingA reliable, corrosion-resistant thru-hull fitting for marine plumbing applications. Made from...

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$16.50 - $16.50
$16.50
$16.50 - $16.50
$16.50