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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 %
$ 1,182.00
$ 1,182.00 - $ 1,182.00
$ 1,182.00
$ 946.00
$ 946.00 - $ 946.00
$ 946.00

Foster PB3-3S/S, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB3-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series ...

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$ 1,182.00
$ 1,182.00 - $ 1,182.00
$ 1,182.00
$ 946.00
$ 946.00 - $ 946.00
$ 946.00
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 %
$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
$ 206.00 - $ 206.00
$ 206.00

Foster PB3-3B, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB3-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
$ 206.00 - $ 206.00
$ 206.00
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 %
$ 519.00
$ 519.00 - $ 519.00
$ 519.00
$ 416.00
$ 416.00 - $ 416.00
$ 416.00

Foster 14S-3, 1/4" Industrial Plug x 3/8" Male NPT, 3 Series, Free Swivel, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 14S-3 is a Brass/Steel 1/4" industrial plug from the Foster 3 Series — the...

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$ 519.00
$ 519.00 - $ 519.00
$ 519.00
$ 416.00
$ 416.00 - $ 416.00
$ 416.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 21% Save %
$ 165.00
$ 165.00 - $ 165.00
$ 165.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00

Foster 10S-3, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Free Swivel, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10S-3 is a Brass/Steel 1/4" industrial plug from the Foster 3 Series — the...

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$ 165.00
$ 165.00 - $ 165.00
$ 165.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 185.00
$ 185.00 - $ 185.00
$ 185.00
$ 148.00
$ 148.00 - $ 148.00
$ 148.00

Foster 12S-3, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, Free Swivel, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 12S-3 is a Brass/Steel 1/4" industrial plug from the Foster 3 Series — the...

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$ 185.00
$ 185.00 - $ 185.00
$ 185.00
$ 148.00
$ 148.00 - $ 148.00
$ 148.00
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 %
$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
$ 70.00 - $ 70.00
$ 70.00

Foster 71-3, 1/4" Industrial Plug x 3/8" Push-On Hose Stem, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 71-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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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 %
$ 98.00
$ 98.00 - $ 98.00
$ 98.00
$ 78.00
$ 78.00 - $ 78.00
$ 78.00

Foster 51-3, 1/4" Industrial Plug x 1/4" Push-On Hose Stem, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 51-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 98.00
$ 98.00 - $ 98.00
$ 98.00
$ 78.00
$ 78.00 - $ 78.00
$ 78.00
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 %
$ 842.00
$ 842.00 - $ 842.00
$ 842.00
$ 674.00
$ 674.00 - $ 674.00
$ 674.00

Foster 17-3S/S, 1/4" Industrial Plug x 3/8" Hose ID, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 17-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 842.00
$ 842.00 - $ 842.00
$ 842.00
$ 674.00
$ 674.00 - $ 674.00
$ 674.00
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 %
$ 138.00
$ 138.00 - $ 138.00
$ 138.00
$ 112.00
$ 112.00 - $ 112.00
$ 112.00

Foster 17-3B, 1/4" Industrial Plug x 3/8" Hose ID, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 17-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 138.00
$ 138.00 - $ 138.00
$ 138.00
$ 112.00
$ 112.00 - $ 112.00
$ 112.00
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 57.00
$ 57.00 - $ 57.00
$ 57.00

Foster 17-3, 1/4" Industrial Plug x 3/8" Hose ID, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 17-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 57.00
$ 57.00 - $ 57.00
$ 57.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 161.00
$ 161.00 - $ 161.00
$ 161.00
$ 129.00
$ 129.00 - $ 129.00
$ 129.00

Foster 165-3, 1/4" Industrial Plug x 5/16" Hose ID, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 165-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 161.00
$ 161.00 - $ 161.00
$ 161.00
$ 129.00
$ 129.00 - $ 129.00
$ 129.00
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 %
$ 151.00
$ 151.00 - $ 151.00
$ 151.00
$ 121.00
$ 121.00 - $ 121.00
$ 121.00

Foster 16-3B, 1/4" Industrial Plug x 1/4" Hose ID, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 16-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 151.00
$ 151.00 - $ 151.00
$ 151.00
$ 121.00
$ 121.00 - $ 121.00
$ 121.00
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 %
$ 64.00
$ 64.00 - $ 64.00
$ 64.00
$ 51.00
$ 51.00 - $ 51.00
$ 51.00

Foster 16-3, 1/4" Industrial Plug x 1/4" Hose ID, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 16-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 64.00
$ 64.00 - $ 64.00
$ 64.00
$ 51.00
$ 51.00 - $ 51.00
$ 51.00
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 %
$ 219.00
$ 219.00 - $ 219.00
$ 219.00
$ 176.00
$ 176.00 - $ 176.00
$ 176.00

Foster 14-3GB, 1/4" Industrial Plug x 3/8" Male NPT, 3 Series, Ball Check, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 14-3GB is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 219.00
$ 219.00 - $ 219.00
$ 219.00
$ 176.00
$ 176.00 - $ 176.00
$ 176.00
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 %
$ 178.00
$ 178.00 - $ 178.00
$ 178.00
$ 142.00
$ 142.00 - $ 142.00
$ 142.00

Foster 14-3B, 1/4" Industrial Plug x 3/8" Male NPT, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 14-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 178.00
$ 178.00 - $ 178.00
$ 178.00
$ 142.00
$ 142.00 - $ 142.00
$ 142.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 57.00
$ 57.00 - $ 57.00
$ 57.00

Foster 14-3, 1/4" Industrial Plug x 3/8" Male NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 14-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 57.00
$ 57.00 - $ 57.00
$ 57.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 215.00
$ 215.00 - $ 215.00
$ 215.00
$ 172.00
$ 172.00 - $ 172.00
$ 172.00

Foster 10-3GS/S, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Ball Check, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3GS/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series ...

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$ 215.00
$ 215.00 - $ 215.00
$ 215.00
$ 172.00
$ 172.00 - $ 172.00
$ 172.00
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 %
$ 161.00
$ 161.00 - $ 161.00
$ 161.00
$ 129.00
$ 129.00 - $ 129.00
$ 129.00

Foster 10-3GS, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Ball Check, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3GS is a Steel 1/4" industrial plug from the Foster 3 Series — the most...

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$ 161.00
$ 161.00 - $ 161.00
$ 161.00
$ 129.00
$ 129.00 - $ 129.00
$ 129.00
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 %
$ 131.00
$ 131.00 - $ 131.00
$ 131.00
$ 106.00
$ 106.00 - $ 106.00
$ 106.00

Foster 10-3GB, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Ball Check, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3GB is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 131.00
$ 131.00 - $ 131.00
$ 131.00
$ 106.00
$ 106.00 - $ 106.00
$ 106.00
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 %
$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00

Foster 10-3G, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Ball Check, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3G is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00
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 %
$ 180.00
$ 180.00 - $ 180.00
$ 180.00
$ 144.00
$ 144.00 - $ 144.00
$ 144.00

Foster 10-3S/S, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 180.00
$ 180.00 - $ 180.00
$ 180.00
$ 144.00
$ 144.00 - $ 144.00
$ 144.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 18% Save %
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 59.00
$ 59.00 - $ 59.00
$ 59.00

Foster 10-3B, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 59.00
$ 59.00 - $ 59.00
$ 59.00
Save 18% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 22% Save %
$ 46.00
$ 46.00 - $ 46.00
$ 46.00
$ 36.00
$ 36.00 - $ 36.00
$ 36.00

Foster 10-3, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 46.00
$ 46.00 - $ 46.00
$ 46.00
$ 36.00
$ 36.00 - $ 36.00
$ 36.00
Save 22% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 236.00
$ 236.00 - $ 236.00
$ 236.00
$ 189.00
$ 189.00 - $ 189.00
$ 189.00

Foster 12-3S/S, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 12-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 236.00
$ 236.00 - $ 236.00
$ 236.00
$ 189.00
$ 189.00 - $ 189.00
$ 189.00
Save 20% Save %

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