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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 %
$ 171.00
$ 171.00 - $ 171.00
$ 171.00
$ 136.00
$ 136.00 - $ 136.00
$ 136.00

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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$ 171.00
$ 171.00 - $ 171.00
$ 171.00
$ 136.00
$ 136.00 - $ 136.00
$ 136.00
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 %
$ 80.00
$ 80.00 - $ 80.00
$ 80.00
$ 65.00
$ 65.00 - $ 65.00
$ 65.00

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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$ 80.00
$ 80.00 - $ 80.00
$ 80.00
$ 65.00
$ 65.00 - $ 65.00
$ 65.00
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 %
$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00

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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$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
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 %
$ 776.00
$ 776.00 - $ 776.00
$ 776.00
$ 621.00
$ 621.00 - $ 621.00
$ 621.00

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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$ 776.00
$ 776.00 - $ 776.00
$ 776.00
$ 621.00
$ 621.00 - $ 621.00
$ 621.00
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 %
$ 127.00
$ 127.00 - $ 127.00
$ 127.00
$ 103.00
$ 103.00 - $ 103.00
$ 103.00

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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$ 127.00
$ 127.00 - $ 127.00
$ 127.00
$ 103.00
$ 103.00 - $ 103.00
$ 103.00
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 %
$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00
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 %
$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00

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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$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00
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 %
$ 139.00
$ 139.00 - $ 139.00
$ 139.00
$ 112.00
$ 112.00 - $ 112.00
$ 112.00

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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$ 139.00
$ 139.00 - $ 139.00
$ 139.00
$ 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 20% Save %
$ 59.00
$ 59.00 - $ 59.00
$ 59.00
$ 47.00
$ 47.00 - $ 47.00
$ 47.00

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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$ 59.00
$ 59.00 - $ 59.00
$ 59.00
$ 47.00
$ 47.00 - $ 47.00
$ 47.00
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 %
$ 202.00
$ 202.00 - $ 202.00
$ 202.00
$ 162.00
$ 162.00 - $ 162.00
$ 162.00

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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$ 202.00
$ 202.00 - $ 202.00
$ 202.00
$ 162.00
$ 162.00 - $ 162.00
$ 162.00
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 %
$ 164.00
$ 164.00 - $ 164.00
$ 164.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00

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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$ 164.00
$ 164.00 - $ 164.00
$ 164.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00
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 %
$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00
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 %
$ 199.00
$ 199.00 - $ 199.00
$ 199.00
$ 159.00
$ 159.00 - $ 159.00
$ 159.00

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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$ 199.00
$ 199.00 - $ 199.00
$ 199.00
$ 159.00
$ 159.00 - $ 159.00
$ 159.00
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 %
$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00

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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$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00
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 %
$ 120.00
$ 120.00 - $ 120.00
$ 120.00
$ 98.00
$ 98.00 - $ 98.00
$ 98.00

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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$ 120.00
$ 120.00 - $ 120.00
$ 120.00
$ 98.00
$ 98.00 - $ 98.00
$ 98.00
Save 18% 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 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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$ 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 %
$ 301.00
$ 301.00 - $ 301.00
$ 301.00
$ 242.00
$ 242.00 - $ 242.00
$ 242.00

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

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

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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
Save 20% Save %
$ 220.00
$ 220.00 - $ 220.00
$ 220.00
$ 176.00
$ 176.00 - $ 176.00
$ 176.00

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

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

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$ 220.00
$ 220.00 - $ 220.00
$ 220.00
$ 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 %
$ 166.00
$ 166.00 - $ 166.00
$ 166.00
$ 133.00
$ 133.00 - $ 133.00
$ 133.00

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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$ 166.00
$ 166.00 - $ 166.00
$ 166.00
$ 133.00
$ 133.00 - $ 133.00
$ 133.00
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 %
$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 54.00
$ 54.00 - $ 54.00
$ 54.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 54.00
$ 54.00 - $ 54.00
$ 54.00
Save 18% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 42.00
$ 42.00 - $ 42.00
$ 42.00
$ 33.00
$ 33.00 - $ 33.00
$ 33.00

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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$ 42.00
$ 42.00 - $ 42.00
$ 42.00
$ 33.00
$ 33.00 - $ 33.00
$ 33.00
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 %
$ 218.00
$ 218.00 - $ 218.00
$ 218.00
$ 174.00
$ 174.00 - $ 174.00
$ 174.00

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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$ 218.00
$ 218.00 - $ 218.00
$ 218.00
$ 174.00
$ 174.00 - $ 174.00
$ 174.00
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 12-3B, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, Brass

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

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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 22% Save %
$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 40.00
$ 40.00 - $ 40.00
$ 40.00

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

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

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$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 40.00
$ 40.00 - $ 40.00
$ 40.00
Save 22% Save %

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