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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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$ 21.59
$ 21.59 - $ 21.59
$ 21.59
$ 17.29
$ 17.29 - $ 17.29
$ 17.29

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

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

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$ 21.59
$ 21.59 - $ 21.59
$ 21.59
$ 17.29
$ 17.29 - $ 17.29
$ 17.29
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$ 22.59
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$ 22.59
$ 18.09
$ 18.09 - $ 18.09
$ 18.09

Foster 3203GS, 3 Series, Industrial Coupler, Automatic, 3/8" Female NPT, Brass, Steel

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

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$ 22.59
$ 22.59 - $ 22.59
$ 22.59
$ 18.09
$ 18.09 - $ 18.09
$ 18.09
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$ 27.79
$ 27.79 - $ 27.79
$ 27.79
$ 22.19
$ 22.19 - $ 22.19
$ 22.19

Foster 3653GS, 3 Series, Industrial Coupler, Automatic, 5/16" Hose Barb, Brass, Steel

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

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$ 27.79
$ 27.79 - $ 27.79
$ 27.79
$ 22.19
$ 22.19 - $ 22.19
$ 22.19
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$ 22.69
$ 22.69 - $ 22.69
$ 22.69
$ 18.19
$ 18.19 - $ 18.19
$ 18.19

Foster 3703GS, 3 Series, Industrial Coupler, Automatic, 3/8" Hose Barb, Brass, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 22.69
$ 22.69 - $ 22.69
$ 22.69
$ 18.19
$ 18.19 - $ 18.19
$ 18.19
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$ 28.19
$ 28.19 - $ 28.19
$ 28.19
$ 22.49
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$ 22.49

Foster 3303GB, 3 Series, Industrial Coupler, Automatic, 3/8" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 28.19
$ 28.19 - $ 28.19
$ 28.19
$ 22.49
$ 22.49 - $ 22.49
$ 22.49
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$ 28.39
$ 28.39 - $ 28.39
$ 28.39
$ 22.69
$ 22.69 - $ 22.69
$ 22.69

Foster 3653GB, 3 Series, Industrial Coupler, Automatic, 5/16" Hose Barb, Brass

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

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$ 28.39
$ 28.39 - $ 28.39
$ 28.39
$ 22.69
$ 22.69 - $ 22.69
$ 22.69
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$ 31.09
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$ 31.09
$ 24.89
$ 24.89 - $ 24.89
$ 24.89

Foster 1513GB, 3 Series, Industrial Coupler, Automatic, 1/4" Hose Barb (Push-On), Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1513GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 31.09
$ 31.09 - $ 31.09
$ 31.09
$ 24.89
$ 24.89 - $ 24.89
$ 24.89
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$ 16.19
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$ 16.19
$ 12.89
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$ 12.89

Foster 1713GB, 3 Series, Industrial Coupler, Automatic, 3/8" Hose Barb (Push-On), Brass

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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$ 16.19
$ 16.19 - $ 16.19
$ 16.19
$ 12.89
$ 12.89 - $ 12.89
$ 12.89
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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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$ 2.09
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$ 2.09
$ 1.69
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$ 1.69

Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic

Protect your 1/4" 3 Series quick plugs when not in use. The Foster 3PDC dust cap keeps dirt, chips, and moisture out of the coupling, helping preve...

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$ 2.09
$ 2.09 - $ 2.09
$ 2.09
$ 1.69
$ 1.69 - $ 1.69
$ 1.69
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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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$ 12.09
$ 12.09 - $ 12.09
$ 12.09
$ 9.69
$ 9.69 - $ 9.69
$ 9.69

Foster PD13-3, 1/4" Industrial Plug x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PD13-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most...

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$ 12.09
$ 12.09 - $ 12.09
$ 12.09
$ 9.69
$ 9.69 - $ 9.69
$ 9.69
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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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$ 10.49
$ 10.49 - $ 10.49
$ 10.49
$ 8.39
$ 8.39 - $ 8.39
$ 8.39

Foster PD11-3, 1/4" Industrial Plug x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PD11-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most...

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$ 10.49
$ 10.49 - $ 10.49
$ 10.49
$ 8.39
$ 8.39 - $ 8.39
$ 8.39
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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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$ 9.59
$ 9.59 - $ 9.59
$ 9.59
$ 7.69
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$ 7.69

Foster PD9-3, 1/4" Industrial Plug x Reusable Hose Fitting, 3/8" ID x 11/16" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PD9-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 9.59
$ 9.59 - $ 9.59
$ 9.59
$ 7.69
$ 7.69 - $ 7.69
$ 7.69
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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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$ 9.19
$ 9.19 - $ 9.19
$ 9.19
$ 7.39
$ 7.39 - $ 7.39
$ 7.39

Foster PD7-3, 1/4" Industrial Plug x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PD7-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 9.19
$ 9.19 - $ 9.19
$ 9.19
$ 7.39
$ 7.39 - $ 7.39
$ 7.39
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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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$ 32.89
$ 32.89 - $ 32.89
$ 32.89
$ 26.29
$ 26.29 - $ 26.29
$ 26.29

Foster PC7-3, 1/4" Industrial Plug x Reusable Hose Fitting, 5/16" ID x 5/8" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PC7-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 32.89
$ 32.89 - $ 32.89
$ 32.89
$ 26.29
$ 26.29 - $ 26.29
$ 26.29
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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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$ 19.39
$ 19.39 - $ 19.39
$ 19.39
$ 15.49
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$ 15.49

Foster PC5-3, 1/4" Industrial Plug x Reusable Hose Fitting, 5/16" ID x 9/16" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PC5-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 19.39
$ 19.39 - $ 19.39
$ 19.39
$ 15.49
$ 15.49 - $ 15.49
$ 15.49
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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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$ 25.79
$ 25.79 - $ 25.79
$ 25.79
$ 20.59
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$ 20.59

Foster PB7-3S/S, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB7-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series ...

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$ 25.79
$ 25.79 - $ 25.79
$ 25.79
$ 20.59
$ 20.59 - $ 20.59
$ 20.59
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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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$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.19
$ 11.19 - $ 11.19
$ 11.19

Foster PB7-3B, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB7-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.19
$ 11.19 - $ 11.19
$ 11.19
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 8.19
$ 8.19 - $ 8.19
$ 8.19
$ 6.59
$ 6.59 - $ 6.59
$ 6.59

Foster PB7-3, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB7-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 8.19
$ 8.19 - $ 8.19
$ 8.19
$ 6.59
$ 6.59 - $ 6.59
$ 6.59
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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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$ 17.19
$ 17.19 - $ 17.19
$ 17.19
$ 13.69
$ 13.69 - $ 13.69
$ 13.69

Foster PB5-3B, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB5-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 17.19
$ 17.19 - $ 17.19
$ 17.19
$ 13.69
$ 13.69 - $ 13.69
$ 13.69
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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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$ 8.99
$ 8.99 - $ 8.99
$ 8.99
$ 7.19
$ 7.19 - $ 7.19
$ 7.19

Foster PB5-3, 1/4" Industrial Plug x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster PB5-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 8.99
$ 8.99 - $ 8.99
$ 8.99
$ 7.19
$ 7.19 - $ 7.19
$ 7.19
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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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$ 62.59
$ 62.59 - $ 62.59
$ 62.59
$ 50.09
$ 50.09 - $ 50.09
$ 50.09

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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$ 62.59
$ 62.59 - $ 62.59
$ 62.59
$ 50.09
$ 50.09 - $ 50.09
$ 50.09
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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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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89

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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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89
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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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$ 27.49
$ 27.49 - $ 27.49
$ 27.49
$ 21.99
$ 21.99 - $ 21.99
$ 21.99

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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$ 27.49
$ 27.49 - $ 27.49
$ 27.49
$ 21.99
$ 21.99 - $ 21.99
$ 21.99
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 %
$ 8.69
$ 8.69 - $ 8.69
$ 8.69
$ 6.89
$ 6.89 - $ 6.89
$ 6.89

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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$ 8.69
$ 8.69 - $ 8.69
$ 8.69
$ 6.89
$ 6.89 - $ 6.89
$ 6.89
Save 21% Save %

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