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Over 50 years of Trusted Marine Service

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.

Browse Products Pumps & Plumbing Ask Parts Desk
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

Thru-Hull-3/4

Thru-Hull-3/4

$5.59 - $5.59
$5.59
$5.59 - $5.59
$5.59
Item locally warehoused

These Thru-Hulls are ideal for salt water use because they are impervious to electrolysis and corrosion. For use with hose to allow water to pass i...

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$5.59 - $5.59
$5.59
$5.59 - $5.59
$5.59
Thru-Hull Fitting 5/8" --

Thru-Hull Fitting 5/8" --

$9.39 - $9.39
$9.39
$9.39 - $9.39
$9.39
Item locally warehoused

These Thru-Hulls are ideal for salt water use because they are impervious to electrolysis and corrosion. For use with hose to allow water to pass i...

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$9.39 - $9.39
$9.39
$9.39 - $9.39
$9.39
Thru-Hull Fitting 1 1/2" --

Thru-Hull Fitting 1 1/2" --

$17.79 - $17.79
$17.79
$17.79 - $17.79
$17.79
Item locally warehoused

These Thru-Hulls are ideal for salt water use because they are impervious to electrolysis and corrosion. For use with hose to allow water to pass i...

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$17.79 - $17.79
$17.79
$17.79 - $17.79
$17.79
Thru-Hull Fitting 1 1/8" --

Thru-Hull Fitting 1 1/8" --

$14.19 - $14.19
$14.19
$14.19 - $14.19
$14.19
Item locally warehoused

These Thru-Hulls are ideal for salt water use because they are impervious to electrolysis and corrosion. For use with hose to allow water to pass i...

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$14.19 - $14.19
$14.19
$14.19 - $14.19
$14.19
Poly In-Line Strainer, 3/4"

Poly In-Line Strainer, 3/4"

$33.59 - $33.59
$33.59
$33.59 - $33.59
$33.59
Item locally warehoused

In-Line Water Strainer contains a removable, clear lens for easy cleaning and changing of filter. Filter is interchangeable with Jabsco. Filter sho...

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$33.59 - $33.59
$33.59
$33.59 - $33.59
$33.59
Poly In-Line Strainer, 5/8"

Poly In-Line Strainer, 5/8"

$39.09 - $39.09
$39.09
$39.09 - $39.09
$39.09
Item locally warehoused

In-Line Water Strainer contains a removable, clear lens for easy cleaning and changing of filter. Filter is interchangeable with Jabsco. Filter sho...

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$39.09 - $39.09
$39.09
$39.09 - $39.09
$39.09
Poly In-Line Strainer, 1/2"

Poly In-Line Strainer, 1/2"

$31.99 - $31.99
$31.99
$31.99 - $31.99
$31.99
Item locally warehoused

In-Line Water Strainer contains a removable, clear lens for easy cleaning and changing of filter. Filter is interchangeable with Jabsco. Filter sho...

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$31.99 - $31.99
$31.99
$31.99 - $31.99
$31.99
Groco WSB1250P Salt-Water Pump Strainer With Stainless Steel Basket

Groco WSB1250P Salt-Water Pump Strainer With Stainless Steel Basket

$142.99 - $142.99
$142.99
$142.99 - $142.99
$142.99
Item locally warehoused

Protect fresh water pumps from debris. White nylon strainer head and clear plastic sight glass. Glass unscrews for filter basket cleaning. Mounting...

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$142.99 - $142.99
$142.99
$142.99 - $142.99
$142.99
Groco WSB1000P Salt-Water Pump Strainer With Stainless Steel Basket

Groco WSB1000P Salt-Water Pump Strainer With Stainless Steel Basket

$137.39 - $137.39
$137.39
$137.39 - $137.39
$137.39
Item locally warehoused

Protect fresh water pumps from debris. White nylon strainer head and clear plastic sight glass. Glass unscrews for filter basket cleaning. Mounting...

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$137.39 - $137.39
$137.39
$137.39 - $137.39
$137.39
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$65.08 - $65.08
$65.08
$65.08 - $65.08
$65.08
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$65.08 - $65.08
$65.08
$65.08 - $65.08
$65.08
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$51.83 - $51.83
$51.83
$51.83 - $51.83
$51.83
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$51.83 - $51.83
$51.83
$51.83 - $51.83
$51.83
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$245.45 - $245.45
$245.45
$245.45 - $245.45
$245.45
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$245.45 - $245.45
$245.45
$245.45 - $245.45
$245.45
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$141.96 - $141.96
$141.96
$141.96 - $141.96
$141.96
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$141.96 - $141.96
$141.96
$141.96 - $141.96
$141.96
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$127.26 - $127.26
$127.26
$127.26 - $127.26
$127.26
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$127.26 - $127.26
$127.26
$127.26 - $127.26
$127.26
Groco STH Bronze Scoop Thru-Hull With Nut

Groco STH Bronze Scoop Thru-Hull With Nut

$88.76 - $88.76
$88.76
$88.76 - $88.76
$88.76
Item locally warehoused

Includes locking nut.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$88.76 - $88.76
$88.76
$88.76 - $88.76
$88.76
Groco IBV750 Bronze Full-Flow In-Line Ball Valve

Groco IBV750 Bronze Full-Flow In-Line Ball Valve

$58.69 - $58.69
$58.69
$58.69 - $58.69
$58.69
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

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$58.69 - $58.69
$58.69
$58.69 - $58.69
$58.69
Groco IBV500 Bronze Full-Flow In-Line Ball Valve

Groco IBV500 Bronze Full-Flow In-Line Ball Valve

$50.19 - $50.19
$50.19
$50.19 - $50.19
$50.19
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$50.19 - $50.19
$50.19
$50.19 - $50.19
$50.19
Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

$63.69 - $63.69
$63.69
$63.69 - $63.69
$63.69
Item locally warehoused

Extra long through hull for installations where hull thickness dictates the use of longer fitting.Locknut included.NOT TO BE USED IN POTABLE WATER ...

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$63.69 - $63.69
$63.69
$63.69 - $63.69
$63.69
Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

$140.59 - $140.59
$140.59
$140.59 - $140.59
$140.59
Item locally warehoused

Extra long through hull for installations where hull thickness dictates the use of longer fitting.Locknut included.NOT TO BE USED IN POTABLE WATER ...

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$140.59 - $140.59
$140.59
$140.59 - $140.59
$140.59
Groco IBV3000 Bronze Full-Flow In-Line Ball Valve

Groco IBV3000 Bronze Full-Flow In-Line Ball Valve

$1,203.39 - $1,203.39
$1,203.39
$1,203.39 - $1,203.39
$1,203.39
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$1,203.39 - $1,203.39
$1,203.39
$1,203.39 - $1,203.39
$1,203.39
Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

$131.69 - $131.69
$131.69
$131.69 - $131.69
$131.69
Item locally warehoused

Extra long through hull for installations where hull thickness dictates the use of longer fitting.Locknut included.NOT TO BE USED IN POTABLE WATER ...

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$131.69 - $131.69
$131.69
$131.69 - $131.69
$131.69
Groco SC2500 Bronze Slotted Strainer With Mount Ring

Groco SC2500 Bronze Slotted Strainer With Mount Ring

$248.59 - $248.59
$248.59
$248.59 - $248.59
$248.59
Item locally warehoused

Mount the ring permanently. Fasten the strainer to the ring and remove as often as needed. Uses 6 #10 fasteners.NOT TO BE USED IN POTABLE WATER SYS...

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$248.59 - $248.59
$248.59
$248.59 - $248.59
$248.59
Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

Groco THXL Bronze Extra-Length Thru-Hull With Nut, NPS Thread

$81.49 - $81.49
$81.49
$81.49 - $81.49
$81.49
Item locally warehoused

Extra long through hull for installations where hull thickness dictates the use of longer fitting.Locknut included.NOT TO BE USED IN POTABLE WATER ...

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$81.49 - $81.49
$81.49
$81.49 - $81.49
$81.49
Groco SC1500 Bronze Slotted Strainer With Mount Ring

Groco SC1500 Bronze Slotted Strainer With Mount Ring

$192.99 - $192.99
$192.99
$192.99 - $192.99
$192.99
Item locally warehoused

Mount the ring permanently. Fasten the strainer to the ring and remove as often as needed. Uses 6 #10 fasteners.NOT TO BE USED IN POTABLE WATER SYS...

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$192.99 - $192.99
$192.99
$192.99 - $192.99
$192.99
Groco IBV2000 Bronze Full-Flow In-Line Ball Valve

Groco IBV2000 Bronze Full-Flow In-Line Ball Valve

$358.89 - $358.89
$358.89
$358.89 - $358.89
$358.89
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$358.89 - $358.89
$358.89
$358.89 - $358.89
$358.89
Groco SC1000 Bronze Slotted Strainer With Mount Ring

Groco SC1000 Bronze Slotted Strainer With Mount Ring

$92.99 - $92.99
$92.99
$92.99 - $92.99
$92.99
Item locally warehoused

Mount the ring permanently. Fasten the strainer to the ring and remove as often as needed. Uses 6 #10 fasteners.NOT TO BE USED IN POTABLE WATER SYS...

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$92.99 - $92.99
$92.99
$92.99 - $92.99
$92.99
Groco IBV1500 Bronze Full-Flow In-Line Ball Valve

Groco IBV1500 Bronze Full-Flow In-Line Ball Valve

$205.79 - $205.79
$205.79
$205.79 - $205.79
$205.79
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$205.79 - $205.79
$205.79
$205.79 - $205.79
$205.79
Groco WSB750 Fresh-Water Pump Strainer With Stainless Steel Basket 3/4"

Groco WSB750 Fresh-Water Pump Strainer With Stainless Steel Basket 3/4"

$87.29 - $87.29
$87.29
$87.29 - $87.29
$87.29
Item locally warehoused

Protect fresh water pumps from debris. White nylon strainer head and clear plastic sight glass. Glass unscrews for filter basket cleaning. Mounting...

View full details
$87.29 - $87.29
$87.29
$87.29 - $87.29
$87.29
Groco IBV1250 Bronze Full-Flow In-Line Ball Valve

Groco IBV1250 Bronze Full-Flow In-Line Ball Valve

$154.39 - $154.39
$154.39
$154.39 - $154.39
$154.39
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$154.39 - $154.39
$154.39
$154.39 - $154.39
$154.39
Groco WSB500P Salt-Water Pump Strainer With Non-Metallic Basket

Groco WSB500P Salt-Water Pump Strainer With Non-Metallic Basket

$90.09 - $90.09
$90.09
$90.09 - $90.09
$90.09
Item locally warehoused

Protect fresh water pumps from debris. White nylon strainer head and clear plastic sight glass. Glass unscrews for filter basket cleaning. Mounting...

View full details
$90.09 - $90.09
$90.09
$90.09 - $90.09
$90.09
Groco WSB500 Salt-Water Pump Strainer With Stainless Steel Basket

Groco WSB500 Salt-Water Pump Strainer With Stainless Steel Basket

$84.49 - $84.49
$84.49
$84.49 - $84.49
$84.49
Item locally warehoused

Protect fresh water pumps from debris. White nylon strainer head and clear plastic sight glass. Glass unscrews for filter basket cleaning. Mounting...

View full details
$84.49 - $84.49
$84.49
$84.49 - $84.49
$84.49
Groco FTH Bronze Flush Thru-Hull With Nut

Groco FTH Bronze Flush Thru-Hull With Nut

$131.79 - $131.79
$131.79
$131.79 - $131.79
$131.79
Item locally warehoused

Includes locknut.Bronze.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$131.79 - $131.79
$131.79
$131.79 - $131.79
$131.79
Groco FTH Bronze Flush Thru-Hull With Nut

Groco FTH Bronze Flush Thru-Hull With Nut

$59.19 - $59.19
$59.19
$59.19 - $59.19
$59.19
Item locally warehoused

Includes locknut.Bronze.NOT TO BE USED IN POTABLE WATER SYSTEMS.

$59.19 - $59.19
$59.19
$59.19 - $59.19
$59.19
Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

$1,278.99 - $1,278.99
$1,278.99
$1,278.99 - $1,278.99
$1,278.99
Item locally warehoused

Features patented field-selectable and changeable direction of rotation-permits installation in otherwise unusable locations. Tri-flange base and m...

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$1,278.99 - $1,278.99
$1,278.99
$1,278.99 - $1,278.99
$1,278.99
Groco IBV1000 Bronze Full-Flow In-Line Ball Valve

Groco IBV1000 Bronze Full-Flow In-Line Ball Valve

$105.89 - $105.89
$105.89
$105.89 - $105.89
$105.89
Item locally warehoused

Patented field reversible handle allows you to select the closed position orientation (clockwise or counterclockwise) that best suits the installat...

View full details
$105.89 - $105.89
$105.89
$105.89 - $105.89
$105.89
Groco ARG1003 Sight Glass With Drain Plug For ARG Strainer

Groco ARG1003 Sight Glass With Drain Plug For ARG Strainer

$144.49 - $144.49
$144.49
$144.49 - $144.49
$144.49
Item locally warehoused

For the ARG series strainers. Maximum psi is 50. Maximum temperature is 225° F. Sight glass includes drain wingnut.

$144.49 - $144.49
$144.49
$144.49 - $144.49
$144.49
Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

$917.49 - $917.49
$917.49
$917.49 - $917.49
$917.49
Item locally warehoused

Features patented field-selectable and changeable direction of rotation-permits installation in otherwise unusable locations. Tri-flange base and m...

View full details
$917.49 - $917.49
$917.49
$917.49 - $917.49
$917.49
Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

$810.59 - $810.59
$810.59
$810.59 - $810.59
$810.59
Item locally warehoused

Features patented field-selectable and changeable direction of rotation-permits installation in otherwise unusable locations. Tri-flange base and m...

View full details
$810.59 - $810.59
$810.59
$810.59 - $810.59
$810.59
Groco BB Backing Block For Flanged Seacock

Groco BB Backing Block For Flanged Seacock

$150.19 - $150.19
$150.19
$150.19 - $150.19
$150.19
Item locally warehoused

Flanged seacock installation is improved with the use of a backing block between the valve flange and the hull. Each size fits multiple seacock siz...

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$150.19 - $150.19
$150.19
$150.19 - $150.19
$150.19
Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

Groco BV Bronze Full-Flow Flanged Ball-Type Seacock

$623.29 - $623.29
$623.29
$623.29 - $623.29
$623.29
Item locally warehoused

Features patented field-selectable and changeable direction of rotation-permits installation in otherwise unusable locations. Tri-flange base and m...

View full details
$623.29 - $623.29
$623.29
$623.29 - $623.29
$623.29
Groco BB Backing Block For Flanged Seacock

Groco BB Backing Block For Flanged Seacock

$128.89 - $128.89
$128.89
$128.89 - $128.89
$128.89
Item locally warehoused

Flanged seacock installation is improved with the use of a backing block between the valve flange and the hull. Each size fits multiple seacock siz...

View full details
$128.89 - $128.89
$128.89
$128.89 - $128.89
$128.89
Groco #304 Stainless Steel Filter Basket

Groco #304 Stainless Steel Filter Basket

$140.29 - $140.29
$140.29
$140.29 - $140.29
$140.29
Item locally warehoused

Spare Basket

$140.29 - $140.29
$140.29
$140.29 - $140.29
$140.29
Groco BB Backing Block For Flanged Seacock

Groco BB Backing Block For Flanged Seacock

$101.59 - $101.59
$101.59
$101.59 - $101.59
$101.59
Item locally warehoused

Flanged seacock installation is improved with the use of a backing block between the valve flange and the hull. Each size fits multiple seacock siz...

View full details
$101.59 - $101.59
$101.59
$101.59 - $101.59
$101.59
Groco #304 Stainless Steel Filter Basket

Groco #304 Stainless Steel Filter Basket

$131.69 - $131.69
$131.69
$131.69 - $131.69
$131.69
Item locally warehoused

Spare Basket

$131.69 - $131.69
$131.69
$131.69 - $131.69
$131.69
Groco #304 Stainless Steel Filter Basket

Groco #304 Stainless Steel Filter Basket

$117.49 - $117.49
$117.49
$117.49 - $117.49
$117.49
Item locally warehoused

Spare Basket

$117.49 - $117.49
$117.49
$117.49 - $117.49
$117.49
Groco #304 Stainless Steel Filter Basket For ARG Strainers

Groco #304 Stainless Steel Filter Basket For ARG Strainers

$111.79 - $111.79
$111.79
$111.79 - $111.79
$111.79
Item locally warehoused

Spare Basket

$111.79 - $111.79
$111.79
$111.79 - $111.79
$111.79
Groco #304 Stainless Steel Filter Basket

Groco #304 Stainless Steel Filter Basket

$102.99 - $102.99
$102.99
$102.99 - $102.99
$102.99
Item locally warehoused

Spare Basket

$102.99 - $102.99
$102.99
$102.99 - $102.99
$102.99
Groco ARG753 Sight Glass With Drain Plug For ARG Strainer

Groco ARG753 Sight Glass With Drain Plug For ARG Strainer

$114.49 - $114.49
$114.49
$114.49 - $114.49
$114.49
Item locally warehoused

For the ARG series strainers. Maximum psi is 50. Maximum temperature is 225° F. Sight glass includes drain wingnut.

$114.49 - $114.49
$114.49
$114.49 - $114.49
$114.49