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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 %
$ 1,173.00
$ 1,173.00 - $ 1,173.00
$ 1,173.00
$ 938.00
$ 938.00 - $ 938.00
$ 938.00

Foster 3603S/S, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 1,173.00
$ 1,173.00 - $ 1,173.00
$ 1,173.00
$ 938.00
$ 938.00 - $ 938.00
$ 938.00
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 %
$ 317.00
$ 317.00 - $ 317.00
$ 317.00
$ 254.00
$ 254.00 - $ 254.00
$ 254.00

Foster 3603S, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 317.00
$ 317.00 - $ 317.00
$ 317.00
$ 254.00
$ 254.00 - $ 254.00
$ 254.00
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 %
$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 226.00
$ 226.00 - $ 226.00
$ 226.00

Foster BL3603, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3603 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 226.00
$ 226.00 - $ 226.00
$ 226.00
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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 %
$ 251.00
$ 251.00 - $ 251.00
$ 251.00
$ 200.00
$ 200.00 - $ 200.00
$ 200.00

Foster 3603, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 251.00
$ 251.00 - $ 251.00
$ 251.00
$ 200.00
$ 200.00 - $ 200.00
$ 200.00
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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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$ 352.00
$ 352.00 - $ 352.00
$ 352.00
$ 280.00
$ 280.00 - $ 280.00
$ 280.00

Foster 1713W, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1713W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 352.00
$ 352.00 - $ 352.00
$ 352.00
$ 280.00
$ 280.00 - $ 280.00
$ 280.00
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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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$ 324.00
$ 324.00 - $ 324.00
$ 324.00
$ 260.00
$ 260.00 - $ 260.00
$ 260.00

Foster BL1713, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL1713 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 324.00
$ 324.00 - $ 324.00
$ 324.00
$ 260.00
$ 260.00 - $ 260.00
$ 260.00
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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 %
$ 282.00
$ 282.00 - $ 282.00
$ 282.00
$ 225.00
$ 225.00 - $ 225.00
$ 225.00

Foster 1713, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1713 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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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 20% Save %
$ 353.00
$ 353.00 - $ 353.00
$ 353.00
$ 284.00
$ 284.00 - $ 284.00
$ 284.00

Foster 1513W, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1513W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 353.00
$ 353.00 - $ 353.00
$ 353.00
$ 284.00
$ 284.00 - $ 284.00
$ 284.00
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 %
$ 317.00
$ 317.00 - $ 317.00
$ 317.00
$ 254.00
$ 254.00 - $ 254.00
$ 254.00

Foster BL1513, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL1513 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 317.00
$ 317.00 - $ 317.00
$ 317.00
$ 254.00
$ 254.00 - $ 254.00
$ 254.00
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 %
$ 279.00
$ 279.00 - $ 279.00
$ 279.00
$ 223.00
$ 223.00 - $ 223.00
$ 223.00

Foster 1513, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1513 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 279.00
$ 279.00 - $ 279.00
$ 279.00
$ 223.00
$ 223.00 - $ 223.00
$ 223.00
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 %
$ 326.00
$ 326.00 - $ 326.00
$ 326.00
$ 261.00
$ 261.00 - $ 261.00
$ 261.00

Foster 3303W, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 326.00
$ 326.00 - $ 326.00
$ 326.00
$ 261.00
$ 261.00 - $ 261.00
$ 261.00
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 %
$ 1,232.00
$ 1,232.00 - $ 1,232.00
$ 1,232.00
$ 985.00
$ 985.00 - $ 985.00
$ 985.00

Foster BL3303S/S, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3303S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 1,232.00
$ 1,232.00 - $ 1,232.00
$ 1,232.00
$ 985.00
$ 985.00 - $ 985.00
$ 985.00
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 %
$ 1,147.00
$ 1,147.00 - $ 1,147.00
$ 1,147.00
$ 917.00
$ 917.00 - $ 917.00
$ 917.00

Foster 3303S/S, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 1,147.00
$ 1,147.00 - $ 1,147.00
$ 1,147.00
$ 917.00
$ 917.00 - $ 917.00
$ 917.00
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 %
$ 298.00
$ 298.00 - $ 298.00
$ 298.00
$ 239.00
$ 239.00 - $ 239.00
$ 239.00

Foster 3303H, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Heat/Viton, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

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$ 298.00
$ 298.00 - $ 298.00
$ 298.00
$ 239.00
$ 239.00 - $ 239.00
$ 239.00
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 %
$ 296.00
$ 296.00 - $ 296.00
$ 296.00
$ 237.00
$ 237.00 - $ 237.00
$ 237.00

Foster BL3303, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3303 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 296.00
$ 296.00 - $ 296.00
$ 296.00
$ 237.00
$ 237.00 - $ 237.00
$ 237.00
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 %
$ 261.00
$ 261.00 - $ 261.00
$ 261.00
$ 209.00
$ 209.00 - $ 209.00
$ 209.00

Foster 3303, 1/4" Industrial Coupler x 3/8" Male NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 261.00
$ 261.00 - $ 261.00
$ 261.00
$ 209.00
$ 209.00 - $ 209.00
$ 209.00
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 %
$ 369.00
$ 369.00 - $ 369.00
$ 369.00
$ 294.00
$ 294.00 - $ 294.00
$ 294.00

Foster BL3103W, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Ball Lock, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3103W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 369.00
$ 369.00 - $ 369.00
$ 369.00
$ 294.00
$ 294.00 - $ 294.00
$ 294.00
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 %
$ 305.00
$ 305.00 - $ 305.00
$ 305.00
$ 244.00
$ 244.00 - $ 244.00
$ 244.00

Foster 3103W, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 305.00
$ 305.00 - $ 305.00
$ 305.00
$ 244.00
$ 244.00 - $ 244.00
$ 244.00
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 %
$ 788.00
$ 788.00 - $ 788.00
$ 788.00
$ 632.00
$ 632.00 - $ 632.00
$ 632.00

Foster 3103S/SLV, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Less Valve, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S/SLV is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 788.00
$ 788.00 - $ 788.00
$ 788.00
$ 632.00
$ 632.00 - $ 632.00
$ 632.00
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 %
$ 828.00
$ 828.00 - $ 828.00
$ 828.00
$ 663.00
$ 663.00 - $ 663.00
$ 663.00

Foster 3103S/SH, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Heat/Viton, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S/SH is a 303 Stainless 1/4" industrial coupler from the Foster 3 Seri...

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$ 828.00
$ 828.00 - $ 828.00
$ 828.00
$ 663.00
$ 663.00 - $ 663.00
$ 663.00
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 %
$ 839.00
$ 839.00 - $ 839.00
$ 839.00
$ 670.00
$ 670.00 - $ 670.00
$ 670.00

Foster BL3103S/S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3103S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 839.00
$ 839.00 - $ 839.00
$ 839.00
$ 670.00
$ 670.00 - $ 670.00
$ 670.00
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 %
$ 783.00
$ 783.00 - $ 783.00
$ 783.00
$ 627.00
$ 627.00 - $ 627.00
$ 627.00

Foster 3103S/S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 783.00
$ 783.00 - $ 783.00
$ 783.00
$ 627.00
$ 627.00 - $ 627.00
$ 627.00
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 %
$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 242.00
$ 242.00 - $ 242.00
$ 242.00

Foster 3103S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 242.00
$ 242.00 - $ 242.00
$ 242.00
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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$ 225.00
$ 225.00 - $ 225.00
$ 225.00
$ 180.00
$ 180.00 - $ 180.00
$ 180.00

Foster 3103LV, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Less Valve, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103LV is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 225.00
$ 225.00 - $ 225.00
$ 225.00
$ 180.00
$ 180.00 - $ 180.00
$ 180.00
Save 20% Save %

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