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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 %
$ 360.00
$ 360.00 - $ 360.00
$ 360.00
$ 288.00
$ 288.00 - $ 288.00
$ 288.00

Foster 3003S, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 360.00
$ 360.00 - $ 360.00
$ 360.00
$ 288.00
$ 288.00 - $ 288.00
$ 288.00
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 %
$ 267.00
$ 267.00 - $ 267.00
$ 267.00
$ 214.00
$ 214.00 - $ 214.00
$ 214.00

Foster 3003LV, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Less Valve, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003LV is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 267.00
$ 267.00 - $ 267.00
$ 267.00
$ 214.00
$ 214.00 - $ 214.00
$ 214.00
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 %
$ 377.00
$ 377.00 - $ 377.00
$ 377.00
$ 301.00
$ 301.00 - $ 301.00
$ 301.00

Foster 3003HW, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Hot Water/Viton, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003HW is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — th...

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$ 377.00
$ 377.00 - $ 377.00
$ 377.00
$ 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 %
$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 240.00
$ 240.00 - $ 240.00
$ 240.00

Foster 3003D, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Dill Valve, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003D is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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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 %
$ 339.00
$ 339.00 - $ 339.00
$ 339.00
$ 271.00
$ 271.00 - $ 271.00
$ 271.00

Foster BL3003, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 339.00
$ 339.00 - $ 339.00
$ 339.00
$ 271.00
$ 271.00 - $ 271.00
$ 271.00
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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 %
$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 227.00
$ 227.00 - $ 227.00
$ 227.00

Foster 3003, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003 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 %
$ 439.00
$ 439.00 - $ 439.00
$ 439.00
$ 352.00
$ 352.00 - $ 352.00
$ 352.00

Foster 2803W, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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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 %
$ 1,127.00
$ 1,127.00 - $ 1,127.00
$ 1,127.00
$ 902.00
$ 902.00 - $ 902.00
$ 902.00

Foster 2803S/S, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 1,127.00
$ 1,127.00 - $ 1,127.00
$ 1,127.00
$ 902.00
$ 902.00 - $ 902.00
$ 902.00
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 %
$ 447.00
$ 447.00 - $ 447.00
$ 447.00
$ 358.00
$ 358.00 - $ 358.00
$ 358.00

Foster 2803S, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 447.00
$ 447.00 - $ 447.00
$ 447.00
$ 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 %
$ 420.00
$ 420.00 - $ 420.00
$ 420.00
$ 337.00
$ 337.00 - $ 337.00
$ 337.00

Foster 2803H, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Heat/Viton, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

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$ 420.00
$ 420.00 - $ 420.00
$ 420.00
$ 337.00
$ 337.00 - $ 337.00
$ 337.00
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
$ 295.00
$ 295.00 - $ 295.00
$ 295.00

Foster BL2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2803 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 369.00
$ 369.00 - $ 369.00
$ 369.00
$ 295.00
$ 295.00 - $ 295.00
$ 295.00
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 %
$ 363.00
$ 363.00 - $ 363.00
$ 363.00
$ 290.00
$ 290.00 - $ 290.00
$ 290.00

Foster 2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 363.00
$ 363.00 - $ 363.00
$ 363.00
$ 290.00
$ 290.00 - $ 290.00
$ 290.00
Save 20% Save %

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