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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 %
$ 230.00
$ 230.00 - $ 230.00
$ 230.00
$ 184.00
$ 184.00 - $ 184.00
$ 184.00

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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$ 230.00
$ 230.00 - $ 230.00
$ 230.00
$ 184.00
$ 184.00 - $ 184.00
$ 184.00
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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 %
$ 271.00
$ 271.00 - $ 271.00
$ 271.00
$ 218.00
$ 218.00 - $ 218.00
$ 218.00

Foster 3103H, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Heat/Viton, Brass/Steel

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

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$ 271.00
$ 271.00 - $ 271.00
$ 271.00
$ 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 Save 20% Save %
$ 250.00
$ 250.00 - $ 250.00
$ 250.00
$ 200.00
$ 200.00 - $ 200.00
$ 200.00

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

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

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$ 250.00
$ 250.00 - $ 250.00
$ 250.00
$ 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 Save 20% Save %
$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 227.00
$ 227.00 - $ 227.00
$ 227.00

Foster BL3103, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3103 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
$ 227.00
$ 227.00 - $ 227.00
$ 227.00
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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 %
$ 243.00
$ 243.00 - $ 243.00
$ 243.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00

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

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

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$ 243.00
$ 243.00 - $ 243.00
$ 243.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00
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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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$ 1,377.00
$ 1,377.00 - $ 1,377.00
$ 1,377.00
$ 1,100.00
$ 1,100.00 - $ 1,100.00
$ 1,100.00

Foster BL2903S/S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2903S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 1,377.00
$ 1,377.00 - $ 1,377.00
$ 1,377.00
$ 1,100.00
$ 1,100.00 - $ 1,100.00
$ 1,100.00
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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 %
$ 1,289.00
$ 1,289.00 - $ 1,289.00
$ 1,289.00
$ 1,031.00
$ 1,031.00 - $ 1,031.00
$ 1,031.00

Foster 2903S/S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 1,289.00
$ 1,289.00 - $ 1,289.00
$ 1,289.00
$ 1,031.00
$ 1,031.00 - $ 1,031.00
$ 1,031.00
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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$ 353.00
$ 353.00 - $ 353.00
$ 353.00
$ 282.00
$ 282.00 - $ 282.00
$ 282.00

Foster 2903S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903S 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
$ 282.00
$ 282.00 - $ 282.00
$ 282.00
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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 %
$ 330.00
$ 330.00 - $ 330.00
$ 330.00
$ 264.00
$ 264.00 - $ 264.00
$ 264.00

Foster 2903H, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Heat/Viton, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

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$ 330.00
$ 330.00 - $ 330.00
$ 330.00
$ 264.00
$ 264.00 - $ 264.00
$ 264.00
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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 %
$ 319.00
$ 319.00 - $ 319.00
$ 319.00
$ 255.00
$ 255.00 - $ 255.00
$ 255.00

Foster BL2903, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2903 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 319.00
$ 319.00 - $ 319.00
$ 319.00
$ 255.00
$ 255.00 - $ 255.00
$ 255.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 19% Save %
$ 293.00
$ 293.00 - $ 293.00
$ 293.00
$ 236.00
$ 236.00 - $ 236.00
$ 236.00

Foster 2903, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 293.00
$ 293.00 - $ 293.00
$ 293.00
$ 236.00
$ 236.00 - $ 236.00
$ 236.00
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 %
$ 339.00
$ 339.00 - $ 339.00
$ 339.00
$ 271.00
$ 271.00 - $ 271.00
$ 271.00

Foster 3203W, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 339.00
$ 339.00 - $ 339.00
$ 339.00
$ 271.00
$ 271.00 - $ 271.00
$ 271.00
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 %
$ 1,206.00
$ 1,206.00 - $ 1,206.00
$ 1,206.00
$ 965.00
$ 965.00 - $ 965.00
$ 965.00

Foster 3203S/SLV, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Less Valve, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203S/SLV is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 1,206.00
$ 1,206.00 - $ 1,206.00
$ 1,206.00
$ 965.00
$ 965.00 - $ 965.00
$ 965.00
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 %
$ 1,289.00
$ 1,289.00 - $ 1,289.00
$ 1,289.00
$ 1,031.00
$ 1,031.00 - $ 1,031.00
$ 1,031.00

Foster BL3203S/S, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3203S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 1,289.00
$ 1,289.00 - $ 1,289.00
$ 1,289.00
$ 1,031.00
$ 1,031.00 - $ 1,031.00
$ 1,031.00
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 %
$ 1,184.00
$ 1,184.00 - $ 1,184.00
$ 1,184.00
$ 947.00
$ 947.00 - $ 947.00
$ 947.00

Foster 3203S/S, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 1,184.00
$ 1,184.00 - $ 1,184.00
$ 1,184.00
$ 947.00
$ 947.00 - $ 947.00
$ 947.00
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 %
$ 253.00
$ 253.00 - $ 253.00
$ 253.00
$ 204.00
$ 204.00 - $ 204.00
$ 204.00

Foster 3203LV, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Less Valve, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203LV is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 253.00
$ 253.00 - $ 253.00
$ 253.00
$ 204.00
$ 204.00 - $ 204.00
$ 204.00
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 %
$ 294.00
$ 294.00 - $ 294.00
$ 294.00
$ 236.00
$ 236.00 - $ 236.00
$ 236.00

Foster 3203H, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Heat/Viton, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

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$ 294.00
$ 294.00 - $ 294.00
$ 294.00
$ 236.00
$ 236.00 - $ 236.00
$ 236.00
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 %
$ 307.00
$ 307.00 - $ 307.00
$ 307.00
$ 245.00
$ 245.00 - $ 245.00
$ 245.00

Foster BL3203, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3203 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 307.00
$ 307.00 - $ 307.00
$ 307.00
$ 245.00
$ 245.00 - $ 245.00
$ 245.00
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 %
$ 271.00
$ 271.00 - $ 271.00
$ 271.00
$ 218.00
$ 218.00 - $ 218.00
$ 218.00

Foster 3203, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 271.00
$ 271.00 - $ 271.00
$ 271.00
$ 218.00
$ 218.00 - $ 218.00
$ 218.00
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
$ 334.00
$ 334.00 - $ 334.00
$ 334.00

Foster BL3003W, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

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$ 418.00
$ 418.00 - $ 418.00
$ 418.00
$ 334.00
$ 334.00 - $ 334.00
$ 334.00
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 %
$ 343.00
$ 343.00 - $ 343.00
$ 343.00
$ 273.00
$ 273.00 - $ 273.00
$ 273.00

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

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

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$ 343.00
$ 343.00 - $ 343.00
$ 343.00
$ 273.00
$ 273.00 - $ 273.00
$ 273.00
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 %
$ 845.00
$ 845.00 - $ 845.00
$ 845.00
$ 676.00
$ 676.00 - $ 676.00
$ 676.00

Foster 3003S/SH, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Heat/Viton, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003S/SH is a 303 Stainless 1/4" industrial coupler from the Foster 3 Seri...

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$ 845.00
$ 845.00 - $ 845.00
$ 845.00
$ 676.00
$ 676.00 - $ 676.00
$ 676.00
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 %
$ 890.00
$ 890.00 - $ 890.00
$ 890.00
$ 712.00
$ 712.00 - $ 712.00
$ 712.00

Foster BL3003S/S, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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$ 890.00
$ 890.00 - $ 890.00
$ 890.00
$ 712.00
$ 712.00 - $ 712.00
$ 712.00
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 %
$ 790.00
$ 790.00 - $ 790.00
$ 790.00
$ 631.00
$ 631.00 - $ 631.00
$ 631.00

Foster 3003S/S, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 790.00
$ 790.00 - $ 790.00
$ 790.00
$ 631.00
$ 631.00 - $ 631.00
$ 631.00
Save 20% Save %

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