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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 %
$ 463.00
$ 463.00 - $ 463.00
$ 463.00
$ 371.00
$ 371.00 - $ 371.00
$ 371.00

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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$ 463.00
$ 463.00 - $ 463.00
$ 463.00
$ 371.00
$ 371.00 - $ 371.00
$ 371.00
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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 %
$ 406.00
$ 406.00 - $ 406.00
$ 406.00
$ 326.00
$ 326.00 - $ 326.00
$ 326.00

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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$ 406.00
$ 406.00 - $ 406.00
$ 406.00
$ 326.00
$ 326.00 - $ 326.00
$ 326.00
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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 %
$ 237.00
$ 237.00 - $ 237.00
$ 237.00
$ 190.00
$ 190.00 - $ 190.00
$ 190.00

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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$ 237.00
$ 237.00 - $ 237.00
$ 237.00
$ 190.00
$ 190.00 - $ 190.00
$ 190.00
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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 %
$ 235.00
$ 235.00 - $ 235.00
$ 235.00
$ 188.00
$ 188.00 - $ 188.00
$ 188.00

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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$ 235.00
$ 235.00 - $ 235.00
$ 235.00
$ 188.00
$ 188.00 - $ 188.00
$ 188.00
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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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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 211.00
$ 211.00 - $ 211.00
$ 211.00

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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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 211.00
$ 211.00 - $ 211.00
$ 211.00
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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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$ 259.00
$ 259.00 - $ 259.00
$ 259.00
$ 207.00
$ 207.00 - $ 207.00
$ 207.00

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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$ 259.00
$ 259.00 - $ 259.00
$ 259.00
$ 207.00
$ 207.00 - $ 207.00
$ 207.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00

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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$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 277.00
$ 277.00 - $ 277.00
$ 277.00
$ 221.00
$ 221.00 - $ 221.00
$ 221.00

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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$ 277.00
$ 277.00 - $ 277.00
$ 277.00
$ 221.00
$ 221.00 - $ 221.00
$ 221.00
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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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$ 226.00
$ 226.00 - $ 226.00
$ 226.00
$ 181.00
$ 181.00 - $ 181.00
$ 181.00

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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$ 226.00
$ 226.00 - $ 226.00
$ 226.00
$ 181.00
$ 181.00 - $ 181.00
$ 181.00
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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 %
$ 308.00
$ 308.00 - $ 308.00
$ 308.00
$ 246.00
$ 246.00 - $ 246.00
$ 246.00

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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$ 308.00
$ 308.00 - $ 308.00
$ 308.00
$ 246.00
$ 246.00 - $ 246.00
$ 246.00
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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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$ 242.00
$ 242.00 - $ 242.00
$ 242.00
$ 193.00
$ 193.00 - $ 193.00
$ 193.00

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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$ 242.00
$ 242.00 - $ 242.00
$ 242.00
$ 193.00
$ 193.00 - $ 193.00
$ 193.00
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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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$ 204.00
$ 204.00 - $ 204.00
$ 204.00
$ 164.00
$ 164.00 - $ 164.00
$ 164.00

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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$ 204.00
$ 204.00 - $ 204.00
$ 204.00
$ 164.00
$ 164.00 - $ 164.00
$ 164.00
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 %
$ 225.00
$ 225.00 - $ 225.00
$ 225.00
$ 179.00
$ 179.00 - $ 179.00
$ 179.00

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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$ 225.00
$ 225.00 - $ 225.00
$ 225.00
$ 179.00
$ 179.00 - $ 179.00
$ 179.00
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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 %
$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 299.00
$ 299.00 - $ 299.00
$ 299.00

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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$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 299.00
$ 299.00 - $ 299.00
$ 299.00
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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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$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
$ 70.00 - $ 70.00
$ 70.00

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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$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
$ 70.00 - $ 70.00
$ 70.00
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 %
$ 423.00
$ 423.00 - $ 423.00
$ 423.00
$ 339.00
$ 339.00 - $ 339.00
$ 339.00

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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$ 423.00
$ 423.00 - $ 423.00
$ 423.00
$ 339.00
$ 339.00 - $ 339.00
$ 339.00
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 %
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 313.00
$ 313.00 - $ 313.00
$ 313.00

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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$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 313.00
$ 313.00 - $ 313.00
$ 313.00
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
$ 332.00
$ 332.00 - $ 332.00
$ 332.00

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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$ 416.00
$ 416.00 - $ 416.00
$ 416.00
$ 332.00
$ 332.00 - $ 332.00
$ 332.00
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 %
$ 385.00
$ 385.00 - $ 385.00
$ 385.00
$ 308.00
$ 308.00 - $ 308.00
$ 308.00

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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$ 385.00
$ 385.00 - $ 385.00
$ 385.00
$ 308.00
$ 308.00 - $ 308.00
$ 308.00
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 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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$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
$ 306.00 - $ 306.00
$ 306.00
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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 %
$ 357.00
$ 357.00 - $ 357.00
$ 357.00
$ 286.00
$ 286.00 - $ 286.00
$ 286.00

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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$ 357.00
$ 357.00 - $ 357.00
$ 357.00
$ 286.00
$ 286.00 - $ 286.00
$ 286.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 376.00
$ 376.00 - $ 376.00
$ 376.00
$ 301.00
$ 301.00 - $ 301.00
$ 301.00

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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$ 376.00
$ 376.00 - $ 376.00
$ 376.00
$ 301.00
$ 301.00 - $ 301.00
$ 301.00
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 %
$ 353.00
$ 353.00 - $ 353.00
$ 353.00
$ 282.00
$ 282.00 - $ 282.00
$ 282.00

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

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

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$ 353.00
$ 353.00 - $ 353.00
$ 353.00
$ 282.00
$ 282.00 - $ 282.00
$ 282.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 572.00
$ 572.00 - $ 572.00
$ 572.00
$ 458.00
$ 458.00 - $ 458.00
$ 458.00

Foster BLSC7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 5/8" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSC7-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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$ 572.00
$ 572.00 - $ 572.00
$ 572.00
$ 458.00
$ 458.00 - $ 458.00
$ 458.00
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