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Foster 3 Series Couplers

The Foster 3 Series is the 1/4" body industrial interchange, the most popular air coupler size for shop and industrial systems. This collection includes 3 Series couplers and plugs in brass, steel, and stainless with NPT, hose barb, push-on, and reusable terminations, plus automatic, sleeve guard, ball check, and dust cap options. Filter by thread, material, and coupler or plug to match your line.

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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 21% Save %
$ 101.00
$ 101.00 - $ 101.00
$ 101.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00

Foster 15-3, 1/4" Industrial Plug x 3/8" Female NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 15-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 101.00
$ 101.00 - $ 101.00
$ 101.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 199.00
$ 199.00 - $ 199.00
$ 199.00
$ 159.00
$ 159.00 - $ 159.00
$ 159.00

Foster 11-3S/S, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 199.00
$ 199.00 - $ 199.00
$ 199.00
$ 159.00
$ 159.00 - $ 159.00
$ 159.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 21% Save %
$ 84.00
$ 84.00 - $ 84.00
$ 84.00
$ 66.00
$ 66.00 - $ 66.00
$ 66.00

Foster 11-3B, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 84.00
$ 84.00 - $ 84.00
$ 84.00
$ 66.00
$ 66.00 - $ 66.00
$ 66.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 17% Save %
$ 47.00
$ 47.00 - $ 47.00
$ 47.00
$ 39.00
$ 39.00 - $ 39.00
$ 39.00

Foster 11-3, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 47.00
$ 47.00 - $ 47.00
$ 47.00
$ 39.00
$ 39.00 - $ 39.00
$ 39.00
Save 17% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 593.00
$ 593.00 - $ 593.00
$ 593.00
$ 475.00
$ 475.00 - $ 475.00
$ 475.00

Foster 13-3S/S, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 593.00
$ 593.00 - $ 593.00
$ 593.00
$ 475.00
$ 475.00 - $ 475.00
$ 475.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 19% Save %
$ 98.00
$ 98.00 - $ 98.00
$ 98.00
$ 79.00
$ 79.00 - $ 79.00
$ 79.00

Foster 13-3B, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 98.00
$ 98.00 - $ 98.00
$ 98.00
$ 79.00
$ 79.00 - $ 79.00
$ 79.00
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 58.00
$ 58.00 - $ 58.00
$ 58.00
$ 46.00
$ 46.00 - $ 46.00
$ 46.00

Foster 13-3, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 58.00
$ 58.00 - $ 58.00
$ 58.00
$ 46.00
$ 46.00 - $ 46.00
$ 46.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 484.00
$ 484.00 - $ 484.00
$ 484.00
$ 388.00
$ 388.00 - $ 388.00
$ 388.00

Foster SD11-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD11-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the...

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$ 484.00
$ 484.00 - $ 484.00
$ 484.00
$ 388.00
$ 388.00 - $ 388.00
$ 388.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 633.00
$ 633.00 - $ 633.00
$ 633.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00

Foster SD11-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD11-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the...

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$ 633.00
$ 633.00 - $ 633.00
$ 633.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 470.00
$ 470.00 - $ 470.00
$ 470.00
$ 376.00
$ 376.00 - $ 376.00
$ 376.00

Foster SD7-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD7-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 470.00
$ 470.00 - $ 470.00
$ 470.00
$ 376.00
$ 376.00 - $ 376.00
$ 376.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 560.00
$ 560.00 - $ 560.00
$ 560.00
$ 449.00
$ 449.00 - $ 449.00
$ 449.00

Foster SD7-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD7-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 560.00
$ 560.00 - $ 560.00
$ 560.00
$ 449.00
$ 449.00 - $ 449.00
$ 449.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 466.00
$ 466.00 - $ 466.00
$ 466.00
$ 374.00
$ 374.00 - $ 374.00
$ 374.00

Foster SB7-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB7-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 466.00
$ 466.00 - $ 466.00
$ 466.00
$ 374.00
$ 374.00 - $ 374.00
$ 374.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 581.00
$ 581.00 - $ 581.00
$ 581.00
$ 466.00
$ 466.00 - $ 466.00
$ 466.00

Foster SB7-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB7-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 581.00
$ 581.00 - $ 581.00
$ 581.00
$ 466.00
$ 466.00 - $ 466.00
$ 466.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 491.00
$ 491.00 - $ 491.00
$ 491.00
$ 393.00
$ 393.00 - $ 393.00
$ 393.00

Foster SB5-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB5-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 491.00
$ 491.00 - $ 491.00
$ 491.00
$ 393.00
$ 393.00 - $ 393.00
$ 393.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 633.00
$ 633.00 - $ 633.00
$ 633.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00

Foster SB5-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB5-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 633.00
$ 633.00 - $ 633.00
$ 633.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 458.00
$ 458.00 - $ 458.00
$ 458.00
$ 366.00
$ 366.00 - $ 366.00
$ 366.00

Foster SB3-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB3-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 458.00
$ 458.00 - $ 458.00
$ 458.00
$ 366.00
$ 366.00 - $ 366.00
$ 366.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 574.00
$ 574.00 - $ 574.00
$ 574.00
$ 459.00
$ 459.00 - $ 459.00
$ 459.00

Foster SB3-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB3-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 574.00
$ 574.00 - $ 574.00
$ 574.00
$ 459.00
$ 459.00 - $ 459.00
$ 459.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 506.00
$ 506.00 - $ 506.00
$ 506.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00

Foster 1713GB, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1713GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 506.00
$ 506.00 - $ 506.00
$ 506.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 541.00
$ 541.00 - $ 541.00
$ 541.00
$ 433.00
$ 433.00 - $ 433.00
$ 433.00

Foster 1513GB, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1513GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 541.00
$ 541.00 - $ 541.00
$ 541.00
$ 433.00
$ 433.00 - $ 433.00
$ 433.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 395.00
$ 395.00 - $ 395.00
$ 395.00
$ 317.00
$ 317.00 - $ 317.00
$ 317.00

Foster 3703GS, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 395.00
$ 395.00 - $ 395.00
$ 395.00
$ 317.00
$ 317.00 - $ 317.00
$ 317.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 517.00
$ 517.00 - $ 517.00
$ 517.00
$ 412.00
$ 412.00 - $ 412.00
$ 412.00

Foster 3703GB, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 517.00
$ 517.00 - $ 517.00
$ 517.00
$ 412.00
$ 412.00 - $ 412.00
$ 412.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 484.00
$ 484.00 - $ 484.00
$ 484.00
$ 386.00
$ 386.00 - $ 386.00
$ 386.00

Foster 3653GS, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3653GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 484.00
$ 484.00 - $ 484.00
$ 484.00
$ 386.00
$ 386.00 - $ 386.00
$ 386.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 494.00
$ 494.00 - $ 494.00
$ 494.00
$ 395.00
$ 395.00 - $ 395.00
$ 395.00

Foster 3653GB, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3653GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 494.00
$ 494.00 - $ 494.00
$ 494.00
$ 395.00
$ 395.00 - $ 395.00
$ 395.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 393.00
$ 393.00 - $ 393.00
$ 393.00
$ 315.00
$ 315.00 - $ 315.00
$ 315.00

Foster 3603GS, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 393.00
$ 393.00 - $ 393.00
$ 393.00
$ 315.00
$ 315.00 - $ 315.00
$ 315.00
Save 20% Save %

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