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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 20% Save %
$ 507.00
$ 507.00 - $ 507.00
$ 507.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00

Foster FMSD11-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSD11-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the...

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$ 507.00
$ 507.00 - $ 507.00
$ 507.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 496.00
$ 496.00 - $ 496.00
$ 496.00
$ 397.00
$ 397.00 - $ 397.00
$ 397.00

Foster FMSD9-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 11/16" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSD9-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 496.00
$ 496.00 - $ 496.00
$ 496.00
$ 397.00
$ 397.00 - $ 397.00
$ 397.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 489.00
$ 489.00 - $ 489.00
$ 489.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00

Foster FMSD7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSD7-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 489.00
$ 489.00 - $ 489.00
$ 489.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 700.00
$ 700.00 - $ 700.00
$ 700.00
$ 560.00
$ 560.00 - $ 560.00
$ 560.00

Foster FMSC7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 5/8" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSC7-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 700.00
$ 700.00 - $ 700.00
$ 700.00
$ 560.00
$ 560.00 - $ 560.00
$ 560.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 700.00
$ 700.00 - $ 700.00
$ 700.00
$ 560.00
$ 560.00 - $ 560.00
$ 560.00

Foster FMSC5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 9/16" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSC5-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 700.00
$ 700.00 - $ 700.00
$ 700.00
$ 560.00
$ 560.00 - $ 560.00
$ 560.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 458.00
$ 458.00 - $ 458.00
$ 458.00
$ 366.00
$ 366.00 - $ 366.00
$ 366.00

Foster FMSB7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSB7-3 is a Brass 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
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 472.00
$ 472.00 - $ 472.00
$ 472.00
$ 378.00
$ 378.00 - $ 378.00
$ 378.00

Foster FMSB5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSB5-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 472.00
$ 472.00 - $ 472.00
$ 472.00
$ 378.00
$ 378.00 - $ 378.00
$ 378.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00

Foster FMSB3-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSB3-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00
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 %
$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00

Foster FM3703S, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3703S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00
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 %
$ 475.00
$ 475.00 - $ 475.00
$ 475.00
$ 381.00
$ 381.00 - $ 381.00
$ 381.00

Foster SL3703, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL3703 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 475.00
$ 475.00 - $ 475.00
$ 475.00
$ 381.00
$ 381.00 - $ 381.00
$ 381.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 411.00
$ 411.00 - $ 411.00
$ 411.00
$ 329.00
$ 329.00 - $ 329.00
$ 329.00

Foster FM3703, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3703 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 411.00
$ 411.00 - $ 411.00
$ 411.00
$ 329.00
$ 329.00 - $ 329.00
$ 329.00
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 %
$ 487.00
$ 487.00 - $ 487.00
$ 487.00
$ 390.00
$ 390.00 - $ 390.00
$ 390.00

Foster SL3653, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL3653 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 487.00
$ 487.00 - $ 487.00
$ 487.00
$ 390.00
$ 390.00 - $ 390.00
$ 390.00
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 %
$ 404.00
$ 404.00 - $ 404.00
$ 404.00
$ 324.00
$ 324.00 - $ 324.00
$ 324.00

Foster FM3653, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3653 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 404.00
$ 404.00 - $ 404.00
$ 404.00
$ 324.00
$ 324.00 - $ 324.00
$ 324.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 468.00
$ 468.00 - $ 468.00
$ 468.00
$ 374.00
$ 374.00 - $ 374.00
$ 374.00

Foster FM3603S, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Automatic, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3603S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 468.00
$ 468.00 - $ 468.00
$ 468.00
$ 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 %
$ 479.00
$ 479.00 - $ 479.00
$ 479.00
$ 383.00
$ 383.00 - $ 383.00
$ 383.00

Foster SL3603, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 479.00
$ 479.00 - $ 479.00
$ 479.00
$ 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 %
$ 397.00
$ 397.00 - $ 397.00
$ 397.00
$ 319.00
$ 319.00 - $ 319.00
$ 319.00

Foster FM3603, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 397.00
$ 397.00 - $ 397.00
$ 397.00
$ 319.00
$ 319.00 - $ 319.00
$ 319.00
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 %
$ 437.00
$ 437.00 - $ 437.00
$ 437.00
$ 350.00
$ 350.00 - $ 350.00
$ 350.00

Foster FM1713W, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Automatic, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM1713W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 437.00
$ 437.00 - $ 437.00
$ 437.00
$ 350.00
$ 350.00 - $ 350.00
$ 350.00
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 %
$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00

Foster SL1713, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL1713 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00
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 %
$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
$ 306.00 - $ 306.00
$ 306.00

Foster FM1713, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM1713 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
$ 306.00 - $ 306.00
$ 306.00
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 %
$ 454.00
$ 454.00 - $ 454.00
$ 454.00
$ 362.00
$ 362.00 - $ 362.00
$ 362.00

Foster SL1513, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL1513 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 454.00
$ 454.00 - $ 454.00
$ 454.00
$ 362.00
$ 362.00 - $ 362.00
$ 362.00
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 %
$ 373.00
$ 373.00 - $ 373.00
$ 373.00
$ 298.00
$ 298.00 - $ 298.00
$ 298.00

Foster FM1513, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM1513 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 373.00
$ 373.00 - $ 373.00
$ 373.00
$ 298.00
$ 298.00 - $ 298.00
$ 298.00
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 %
$ 451.00
$ 451.00 - $ 451.00
$ 451.00
$ 360.00
$ 360.00 - $ 360.00
$ 360.00

Foster FM3303W, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Automatic, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3303W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 451.00
$ 451.00 - $ 451.00
$ 451.00
$ 360.00
$ 360.00 - $ 360.00
$ 360.00
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 %
$ 447.00
$ 447.00 - $ 447.00
$ 447.00
$ 357.00
$ 357.00 - $ 357.00
$ 357.00

Foster SL3303, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 447.00
$ 447.00 - $ 447.00
$ 447.00
$ 357.00
$ 357.00 - $ 357.00
$ 357.00
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 %
$ 390.00
$ 390.00 - $ 390.00
$ 390.00
$ 312.00
$ 312.00 - $ 312.00
$ 312.00

Foster FM3303, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 390.00
$ 390.00 - $ 390.00
$ 390.00
$ 312.00
$ 312.00 - $ 312.00
$ 312.00
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