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

Foster FM2803W, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Automatic, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM2803W 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
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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 %
$ 454.00
$ 454.00 - $ 454.00
$ 454.00
$ 363.00
$ 363.00 - $ 363.00
$ 363.00

Foster SL2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL2803 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
$ 363.00
$ 363.00 - $ 363.00
$ 363.00
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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 %
$ 503.00
$ 503.00 - $ 503.00
$ 503.00
$ 403.00
$ 403.00 - $ 403.00
$ 403.00

Foster FM2803S, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Automatic, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM2803S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 503.00
$ 503.00 - $ 503.00
$ 503.00
$ 403.00
$ 403.00 - $ 403.00
$ 403.00
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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 %
$ 441.00
$ 441.00 - $ 441.00
$ 441.00
$ 354.00
$ 354.00 - $ 354.00
$ 354.00

Foster FM2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Automatic, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM2803 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 441.00
$ 441.00 - $ 441.00
$ 441.00
$ 354.00
$ 354.00 - $ 354.00
$ 354.00
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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 %
$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
$ 206.00 - $ 206.00
$ 206.00

Foster SG3703, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3703 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
$ 206.00 - $ 206.00
$ 206.00
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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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$ 255.00
$ 255.00 - $ 255.00
$ 255.00
$ 204.00
$ 204.00 - $ 204.00
$ 204.00

Foster SG3603, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 255.00
$ 255.00 - $ 255.00
$ 255.00
$ 204.00
$ 204.00 - $ 204.00
$ 204.00
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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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$ 286.00
$ 286.00 - $ 286.00
$ 286.00
$ 229.00
$ 229.00 - $ 229.00
$ 229.00

Foster SG1713, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG1713 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 286.00
$ 286.00 - $ 286.00
$ 286.00
$ 229.00
$ 229.00 - $ 229.00
$ 229.00
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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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$ 282.00
$ 282.00 - $ 282.00
$ 282.00
$ 225.00
$ 225.00 - $ 225.00
$ 225.00

Foster SG1513, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG1513 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 282.00
$ 282.00 - $ 282.00
$ 282.00
$ 225.00
$ 225.00 - $ 225.00
$ 225.00
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 %
$ 267.00
$ 267.00 - $ 267.00
$ 267.00
$ 212.00
$ 212.00 - $ 212.00
$ 212.00

Foster SG3303, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 267.00
$ 267.00 - $ 267.00
$ 267.00
$ 212.00
$ 212.00 - $ 212.00
$ 212.00
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 %
$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 240.00
$ 240.00 - $ 240.00
$ 240.00

Foster SG3103D, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Sleeve Guard, Dill Valve, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3103D is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 240.00
$ 240.00 - $ 240.00
$ 240.00
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 %
$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 197.00
$ 197.00 - $ 197.00
$ 197.00

Foster SG3103, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3103 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 197.00
$ 197.00 - $ 197.00
$ 197.00
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 %
$ 335.00
$ 335.00 - $ 335.00
$ 335.00
$ 267.00
$ 267.00 - $ 267.00
$ 267.00

Foster SG2903, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG2903 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 335.00
$ 335.00 - $ 335.00
$ 335.00
$ 267.00
$ 267.00 - $ 267.00
$ 267.00
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 %
$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 210.00
$ 210.00 - $ 210.00
$ 210.00

Foster SG3203, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3203 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 210.00
$ 210.00 - $ 210.00
$ 210.00
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 %
$ 221.00
$ 221.00 - $ 221.00
$ 221.00
$ 178.00
$ 178.00 - $ 178.00
$ 178.00

Foster SG3003LV, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Sleeve Guard, Less Valve, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3003LV is a Brass 1/4" industrial coupler from the Foster 3 Series — the...

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$ 221.00
$ 221.00 - $ 221.00
$ 221.00
$ 178.00
$ 178.00 - $ 178.00
$ 178.00
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 244.00
$ 244.00 - $ 244.00
$ 244.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00

Foster SG3003, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3003 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 244.00
$ 244.00 - $ 244.00
$ 244.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00
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 %
$ 407.00
$ 407.00 - $ 407.00
$ 407.00
$ 325.00
$ 325.00 - $ 325.00
$ 325.00

Foster SG2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Sleeve Guard, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG2803 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 407.00
$ 407.00 - $ 407.00
$ 407.00
$ 325.00
$ 325.00 - $ 325.00
$ 325.00
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 %
$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00

Foster 3SDC, 1/4" 3 Series Socket Dust Cap, Steel

Protect your 1/4" 3 Series quick sockets when not in use. The Foster 3SDC dust cap keeps dirt, chips, and moisture out of the coupling, helping pre...

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$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00
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 %
$ 459.00
$ 459.00 - $ 459.00
$ 459.00
$ 369.00
$ 369.00 - $ 369.00
$ 369.00

Foster BLSD13-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSD13-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series...

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$ 459.00
$ 459.00 - $ 459.00
$ 459.00
$ 369.00
$ 369.00 - $ 369.00
$ 369.00
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 %
$ 425.00
$ 425.00 - $ 425.00
$ 425.00
$ 340.00
$ 340.00 - $ 340.00
$ 340.00

Foster SD13-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD13-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 425.00
$ 425.00 - $ 425.00
$ 425.00
$ 340.00
$ 340.00 - $ 340.00
$ 340.00
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 %
$ 452.00
$ 452.00 - $ 452.00
$ 452.00
$ 361.00
$ 361.00 - $ 361.00
$ 361.00

Foster BLSD11-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSD11-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series...

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$ 452.00
$ 452.00 - $ 452.00
$ 452.00
$ 361.00
$ 361.00 - $ 361.00
$ 361.00
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 %
$ 418.00
$ 418.00 - $ 418.00
$ 418.00
$ 335.00
$ 335.00 - $ 335.00
$ 335.00

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

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

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$ 418.00
$ 418.00 - $ 418.00
$ 418.00
$ 335.00
$ 335.00 - $ 335.00
$ 335.00
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 BLSD9-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 11/16" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSD9-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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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 %
$ 388.00
$ 388.00 - $ 388.00
$ 388.00
$ 310.00
$ 310.00 - $ 310.00
$ 310.00

Foster SD9-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 11/16" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD9-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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$ 388.00
$ 388.00 - $ 388.00
$ 388.00
$ 310.00
$ 310.00 - $ 310.00
$ 310.00
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 %
$ 408.00
$ 408.00 - $ 408.00
$ 408.00
$ 327.00
$ 327.00 - $ 327.00
$ 327.00

Foster BLSD7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSD7-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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$ 408.00
$ 408.00 - $ 408.00
$ 408.00
$ 327.00
$ 327.00 - $ 327.00
$ 327.00
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