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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 %
$ 323.00
$ 323.00 - $ 323.00
$ 323.00
$ 259.00
$ 259.00 - $ 259.00
$ 259.00

Foster 3653, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3653 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 323.00
$ 323.00 - $ 323.00
$ 323.00
$ 259.00
$ 259.00 - $ 259.00
$ 259.00
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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 %
$ 335.00
$ 335.00 - $ 335.00
$ 335.00
$ 269.00
$ 269.00 - $ 269.00
$ 269.00

Foster 3603W, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Water, Brass/SS

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

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$ 335.00
$ 335.00 - $ 335.00
$ 335.00
$ 269.00
$ 269.00 - $ 269.00
$ 269.00
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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 %
$ 1,274.00
$ 1,274.00 - $ 1,274.00
$ 1,274.00
$ 1,019.00
$ 1,019.00 - $ 1,019.00
$ 1,019.00

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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$ 1,274.00
$ 1,274.00 - $ 1,274.00
$ 1,274.00
$ 1,019.00
$ 1,019.00 - $ 1,019.00
$ 1,019.00
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 %
$ 344.00
$ 344.00 - $ 344.00
$ 344.00
$ 276.00
$ 276.00 - $ 276.00
$ 276.00

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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$ 344.00
$ 344.00 - $ 344.00
$ 344.00
$ 276.00
$ 276.00 - $ 276.00
$ 276.00
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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 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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$ 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
Save 20% Save %
$ 272.00
$ 272.00 - $ 272.00
$ 272.00
$ 218.00
$ 218.00 - $ 218.00
$ 218.00

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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$ 272.00
$ 272.00 - $ 272.00
$ 272.00
$ 218.00
$ 218.00 - $ 218.00
$ 218.00
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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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$ 382.00
$ 382.00 - $ 382.00
$ 382.00
$ 305.00
$ 305.00 - $ 305.00
$ 305.00

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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$ 382.00
$ 382.00 - $ 382.00
$ 382.00
$ 305.00
$ 305.00 - $ 305.00
$ 305.00
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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
$ 282.00
$ 282.00 - $ 282.00
$ 282.00

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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$ 352.00
$ 352.00 - $ 352.00
$ 352.00
$ 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
Save 20% Save %
$ 306.00
$ 306.00 - $ 306.00
$ 306.00
$ 244.00
$ 244.00 - $ 244.00
$ 244.00

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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$ 306.00
$ 306.00 - $ 306.00
$ 306.00
$ 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 %
$ 384.00
$ 384.00 - $ 384.00
$ 384.00
$ 308.00
$ 308.00 - $ 308.00
$ 308.00

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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$ 384.00
$ 384.00 - $ 384.00
$ 384.00
$ 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 %
$ 344.00
$ 344.00 - $ 344.00
$ 344.00
$ 276.00
$ 276.00 - $ 276.00
$ 276.00

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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$ 344.00
$ 344.00 - $ 344.00
$ 344.00
$ 276.00
$ 276.00 - $ 276.00
$ 276.00
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 %
$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 242.00
$ 242.00 - $ 242.00
$ 242.00

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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$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 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
Save 20% Save %
$ 354.00
$ 354.00 - $ 354.00
$ 354.00
$ 284.00
$ 284.00 - $ 284.00
$ 284.00

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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$ 354.00
$ 354.00 - $ 354.00
$ 354.00
$ 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 %
$ 1,338.00
$ 1,338.00 - $ 1,338.00
$ 1,338.00
$ 1,070.00
$ 1,070.00 - $ 1,070.00
$ 1,070.00

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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$ 1,338.00
$ 1,338.00 - $ 1,338.00
$ 1,338.00
$ 1,070.00
$ 1,070.00 - $ 1,070.00
$ 1,070.00
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 %
$ 1,245.00
$ 1,245.00 - $ 1,245.00
$ 1,245.00
$ 996.00
$ 996.00 - $ 996.00
$ 996.00

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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$ 1,245.00
$ 1,245.00 - $ 1,245.00
$ 1,245.00
$ 996.00
$ 996.00 - $ 996.00
$ 996.00
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 %
$ 323.00
$ 323.00 - $ 323.00
$ 323.00
$ 259.00
$ 259.00 - $ 259.00
$ 259.00

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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$ 323.00
$ 323.00 - $ 323.00
$ 323.00
$ 259.00
$ 259.00 - $ 259.00
$ 259.00
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 %
$ 322.00
$ 322.00 - $ 322.00
$ 322.00
$ 257.00
$ 257.00 - $ 257.00
$ 257.00

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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$ 322.00
$ 322.00 - $ 322.00
$ 322.00
$ 257.00
$ 257.00 - $ 257.00
$ 257.00
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
$ 227.00
$ 227.00 - $ 227.00
$ 227.00

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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$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 227.00
$ 227.00 - $ 227.00
$ 227.00
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 %
$ 401.00
$ 401.00 - $ 401.00
$ 401.00
$ 320.00
$ 320.00 - $ 320.00
$ 320.00

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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$ 401.00
$ 401.00 - $ 401.00
$ 401.00
$ 320.00
$ 320.00 - $ 320.00
$ 320.00
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 %
$ 331.00
$ 331.00 - $ 331.00
$ 331.00
$ 265.00
$ 265.00 - $ 265.00
$ 265.00

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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$ 331.00
$ 331.00 - $ 331.00
$ 331.00
$ 265.00
$ 265.00 - $ 265.00
$ 265.00
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 %
$ 856.00
$ 856.00 - $ 856.00
$ 856.00
$ 686.00
$ 686.00 - $ 686.00
$ 686.00

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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$ 856.00
$ 856.00 - $ 856.00
$ 856.00
$ 686.00
$ 686.00 - $ 686.00
$ 686.00
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 %
$ 900.00
$ 900.00 - $ 900.00
$ 900.00
$ 720.00
$ 720.00 - $ 720.00
$ 720.00

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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$ 900.00
$ 900.00 - $ 900.00
$ 900.00
$ 720.00
$ 720.00 - $ 720.00
$ 720.00
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 %
$ 911.00
$ 911.00 - $ 911.00
$ 911.00
$ 728.00
$ 728.00 - $ 728.00
$ 728.00

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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$ 911.00
$ 911.00 - $ 911.00
$ 911.00
$ 728.00
$ 728.00 - $ 728.00
$ 728.00
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 %
$ 851.00
$ 851.00 - $ 851.00
$ 851.00
$ 680.00
$ 680.00 - $ 680.00
$ 680.00

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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$ 851.00
$ 851.00 - $ 851.00
$ 851.00
$ 680.00
$ 680.00 - $ 680.00
$ 680.00
Save 20% Save %

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