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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 %
$ 573.00
$ 573.00 - $ 573.00
$ 573.00
$ 458.00
$ 458.00 - $ 458.00
$ 458.00

Foster SLSB3-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SLSB3-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 573.00
$ 573.00 - $ 573.00
$ 573.00
$ 458.00
$ 458.00 - $ 458.00
$ 458.00
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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 %
$ 584.00
$ 584.00 - $ 584.00
$ 584.00
$ 467.00
$ 467.00 - $ 467.00
$ 467.00

Foster FMSD13-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FMSD13-3 is a Brass 1/4" industrial coupler from the Foster 3 Series — the...

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$ 584.00
$ 584.00 - $ 584.00
$ 584.00
$ 467.00
$ 467.00 - $ 467.00
$ 467.00
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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 %
$ 550.00
$ 550.00 - $ 550.00
$ 550.00
$ 441.00
$ 441.00 - $ 441.00
$ 441.00

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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$ 550.00
$ 550.00 - $ 550.00
$ 550.00
$ 441.00
$ 441.00 - $ 441.00
$ 441.00
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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 %
$ 539.00
$ 539.00 - $ 539.00
$ 539.00
$ 431.00
$ 431.00 - $ 431.00
$ 431.00

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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$ 539.00
$ 539.00 - $ 539.00
$ 539.00
$ 431.00
$ 431.00 - $ 431.00
$ 431.00
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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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$ 531.00
$ 531.00 - $ 531.00
$ 531.00
$ 426.00
$ 426.00 - $ 426.00
$ 426.00

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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$ 531.00
$ 531.00 - $ 531.00
$ 531.00
$ 426.00
$ 426.00 - $ 426.00
$ 426.00
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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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$ 760.00
$ 760.00 - $ 760.00
$ 760.00
$ 609.00
$ 609.00 - $ 609.00
$ 609.00

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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$ 760.00
$ 760.00 - $ 760.00
$ 760.00
$ 609.00
$ 609.00 - $ 609.00
$ 609.00
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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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$ 760.00
$ 760.00 - $ 760.00
$ 760.00
$ 609.00
$ 609.00 - $ 609.00
$ 609.00

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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$ 760.00
$ 760.00 - $ 760.00
$ 760.00
$ 609.00
$ 609.00 - $ 609.00
$ 609.00
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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 %
$ 497.00
$ 497.00 - $ 497.00
$ 497.00
$ 397.00
$ 397.00 - $ 397.00
$ 397.00

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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$ 497.00
$ 497.00 - $ 497.00
$ 497.00
$ 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 %
$ 513.00
$ 513.00 - $ 513.00
$ 513.00
$ 411.00
$ 411.00 - $ 411.00
$ 411.00

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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$ 513.00
$ 513.00 - $ 513.00
$ 513.00
$ 411.00
$ 411.00 - $ 411.00
$ 411.00
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 %
$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00

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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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
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 %
$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00

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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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
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 %
$ 516.00
$ 516.00 - $ 516.00
$ 516.00
$ 414.00
$ 414.00 - $ 414.00
$ 414.00

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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$ 516.00
$ 516.00 - $ 516.00
$ 516.00
$ 414.00
$ 414.00 - $ 414.00
$ 414.00
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 %
$ 446.00
$ 446.00 - $ 446.00
$ 446.00
$ 358.00
$ 358.00 - $ 358.00
$ 358.00

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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$ 446.00
$ 446.00 - $ 446.00
$ 446.00
$ 358.00
$ 358.00 - $ 358.00
$ 358.00
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 %
$ 530.00
$ 530.00 - $ 530.00
$ 530.00
$ 424.00
$ 424.00 - $ 424.00
$ 424.00

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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$ 530.00
$ 530.00 - $ 530.00
$ 530.00
$ 424.00
$ 424.00 - $ 424.00
$ 424.00
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 %
$ 439.00
$ 439.00 - $ 439.00
$ 439.00
$ 352.00
$ 352.00 - $ 352.00
$ 352.00

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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$ 439.00
$ 439.00 - $ 439.00
$ 439.00
$ 352.00
$ 352.00 - $ 352.00
$ 352.00
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 %
$ 509.00
$ 509.00 - $ 509.00
$ 509.00
$ 407.00
$ 407.00 - $ 407.00
$ 407.00

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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$ 509.00
$ 509.00 - $ 509.00
$ 509.00
$ 407.00
$ 407.00 - $ 407.00
$ 407.00
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 %
$ 520.00
$ 520.00 - $ 520.00
$ 520.00
$ 416.00
$ 416.00 - $ 416.00
$ 416.00

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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$ 520.00
$ 520.00 - $ 520.00
$ 520.00
$ 416.00
$ 416.00 - $ 416.00
$ 416.00
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 %
$ 431.00
$ 431.00 - $ 431.00
$ 431.00
$ 346.00
$ 346.00 - $ 346.00
$ 346.00

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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$ 431.00
$ 431.00 - $ 431.00
$ 431.00
$ 346.00
$ 346.00 - $ 346.00
$ 346.00
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
$ 380.00
$ 380.00 - $ 380.00
$ 380.00

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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$ 475.00
$ 475.00 - $ 475.00
$ 475.00
$ 380.00
$ 380.00 - $ 380.00
$ 380.00
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 %
$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00

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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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
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 %
$ 416.00
$ 416.00 - $ 416.00
$ 416.00
$ 333.00
$ 333.00 - $ 333.00
$ 333.00

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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$ 416.00
$ 416.00 - $ 416.00
$ 416.00
$ 333.00
$ 333.00 - $ 333.00
$ 333.00
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
$ 393.00
$ 393.00 - $ 393.00
$ 393.00

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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$ 494.00
$ 494.00 - $ 494.00
$ 494.00
$ 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 %
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
$ 324.00
$ 324.00 - $ 324.00
$ 324.00

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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$ 405.00
$ 405.00 - $ 405.00
$ 405.00
$ 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
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$ 490.00
$ 490.00 - $ 490.00
$ 490.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00

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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$ 490.00
$ 490.00 - $ 490.00
$ 490.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
Save 20% Save %

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