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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 %
$ 52.00
$ 52.00 - $ 52.00
$ 52.00
$ 41.00
$ 41.00 - $ 41.00
$ 41.00

Foster 12-3, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 12-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 52.00
$ 52.00 - $ 52.00
$ 52.00
$ 41.00
$ 41.00 - $ 41.00
$ 41.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 21% Save %
$ 104.00
$ 104.00 - $ 104.00
$ 104.00
$ 82.00
$ 82.00 - $ 82.00
$ 82.00

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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$ 104.00
$ 104.00 - $ 104.00
$ 104.00
$ 82.00
$ 82.00 - $ 82.00
$ 82.00
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 %
$ 203.00
$ 203.00 - $ 203.00
$ 203.00
$ 162.00
$ 162.00 - $ 162.00
$ 162.00

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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$ 203.00
$ 203.00 - $ 203.00
$ 203.00
$ 162.00
$ 162.00 - $ 162.00
$ 162.00
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 %
$ 86.00
$ 86.00 - $ 86.00
$ 86.00
$ 68.00
$ 68.00 - $ 68.00
$ 68.00

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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$ 86.00
$ 86.00 - $ 86.00
$ 86.00
$ 68.00
$ 68.00 - $ 68.00
$ 68.00
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 %
$ 48.00
$ 48.00 - $ 48.00
$ 48.00
$ 40.00
$ 40.00 - $ 40.00
$ 40.00

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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$ 48.00
$ 48.00 - $ 48.00
$ 48.00
$ 40.00
$ 40.00 - $ 40.00
$ 40.00
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 %
$ 608.00
$ 608.00 - $ 608.00
$ 608.00
$ 487.00
$ 487.00 - $ 487.00
$ 487.00

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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$ 608.00
$ 608.00 - $ 608.00
$ 608.00
$ 487.00
$ 487.00 - $ 487.00
$ 487.00
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 %
$ 100.00
$ 100.00 - $ 100.00
$ 100.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00

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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$ 100.00
$ 100.00 - $ 100.00
$ 100.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00
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 %
$ 59.00
$ 59.00 - $ 59.00
$ 59.00
$ 47.00
$ 47.00 - $ 47.00
$ 47.00

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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$ 59.00
$ 59.00 - $ 59.00
$ 59.00
$ 47.00
$ 47.00 - $ 47.00
$ 47.00
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 %
$ 495.00
$ 495.00 - $ 495.00
$ 495.00
$ 398.00
$ 398.00 - $ 398.00
$ 398.00

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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$ 495.00
$ 495.00 - $ 495.00
$ 495.00
$ 398.00
$ 398.00 - $ 398.00
$ 398.00
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 %
$ 649.00
$ 649.00 - $ 649.00
$ 649.00
$ 519.00
$ 519.00 - $ 519.00
$ 519.00

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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$ 649.00
$ 649.00 - $ 649.00
$ 649.00
$ 519.00
$ 519.00 - $ 519.00
$ 519.00
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 %
$ 481.00
$ 481.00 - $ 481.00
$ 481.00
$ 385.00
$ 385.00 - $ 385.00
$ 385.00

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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$ 481.00
$ 481.00 - $ 481.00
$ 481.00
$ 385.00
$ 385.00 - $ 385.00
$ 385.00
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
$ 460.00
$ 460.00 - $ 460.00
$ 460.00

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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$ 574.00
$ 574.00 - $ 574.00
$ 574.00
$ 460.00
$ 460.00 - $ 460.00
$ 460.00
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 %
$ 478.00
$ 478.00 - $ 478.00
$ 478.00
$ 383.00
$ 383.00 - $ 383.00
$ 383.00

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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$ 478.00
$ 478.00 - $ 478.00
$ 478.00
$ 383.00
$ 383.00 - $ 383.00
$ 383.00
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 %
$ 595.00
$ 595.00 - $ 595.00
$ 595.00
$ 478.00
$ 478.00 - $ 478.00
$ 478.00

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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$ 595.00
$ 595.00 - $ 595.00
$ 595.00
$ 478.00
$ 478.00 - $ 478.00
$ 478.00
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 %
$ 503.00
$ 503.00 - $ 503.00
$ 503.00
$ 403.00
$ 403.00 - $ 403.00
$ 403.00

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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$ 503.00
$ 503.00 - $ 503.00
$ 503.00
$ 403.00
$ 403.00 - $ 403.00
$ 403.00
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 %
$ 649.00
$ 649.00 - $ 649.00
$ 649.00
$ 519.00
$ 519.00 - $ 519.00
$ 519.00

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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$ 649.00
$ 649.00 - $ 649.00
$ 649.00
$ 519.00
$ 519.00 - $ 519.00
$ 519.00
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 %
$ 469.00
$ 469.00 - $ 469.00
$ 469.00
$ 374.00
$ 374.00 - $ 374.00
$ 374.00

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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$ 469.00
$ 469.00 - $ 469.00
$ 469.00
$ 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 %
$ 588.00
$ 588.00 - $ 588.00
$ 588.00
$ 471.00
$ 471.00 - $ 471.00
$ 471.00

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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$ 588.00
$ 588.00 - $ 588.00
$ 588.00
$ 471.00
$ 471.00 - $ 471.00
$ 471.00
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 %
$ 519.00
$ 519.00 - $ 519.00
$ 519.00
$ 415.00
$ 415.00 - $ 415.00
$ 415.00

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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$ 519.00
$ 519.00 - $ 519.00
$ 519.00
$ 415.00
$ 415.00 - $ 415.00
$ 415.00
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 %
$ 554.00
$ 554.00 - $ 554.00
$ 554.00
$ 444.00
$ 444.00 - $ 444.00
$ 444.00

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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$ 554.00
$ 554.00 - $ 554.00
$ 554.00
$ 444.00
$ 444.00 - $ 444.00
$ 444.00
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 %
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
$ 324.00
$ 324.00 - $ 324.00
$ 324.00

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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$ 405.00
$ 405.00 - $ 405.00
$ 405.00
$ 324.00
$ 324.00 - $ 324.00
$ 324.00
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 %
$ 529.00
$ 529.00 - $ 529.00
$ 529.00
$ 422.00
$ 422.00 - $ 422.00
$ 422.00

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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$ 529.00
$ 529.00 - $ 529.00
$ 529.00
$ 422.00
$ 422.00 - $ 422.00
$ 422.00
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 %
$ 495.00
$ 495.00 - $ 495.00
$ 495.00
$ 396.00
$ 396.00 - $ 396.00
$ 396.00

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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$ 495.00
$ 495.00 - $ 495.00
$ 495.00
$ 396.00
$ 396.00 - $ 396.00
$ 396.00
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
$ 405.00
$ 405.00 - $ 405.00
$ 405.00

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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$ 506.00
$ 506.00 - $ 506.00
$ 506.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
Save 20% Save %

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