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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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$ 2.39
$ 2.39 - $ 2.39
$ 2.39
$ 1.89
$ 1.89 - $ 1.89
$ 1.89

Foster 10-3, 3 Series, Industrial Plug, 1/4" Male NPT, 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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$ 2.39
$ 2.39 - $ 2.39
$ 2.39
$ 1.89
$ 1.89 - $ 1.89
$ 1.89
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$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99

Foster 3003, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, 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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$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99
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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 3.09
$ 3.09 - $ 3.09
$ 3.09

Foster 10-3B, 3 Series, Industrial Plug, 1/4" Male NPT, 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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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 3.09
$ 3.09 - $ 3.09
$ 3.09
Save 18% Save %
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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89

Foster 3103, 3 Series, Industrial Coupler, Manual, 1/4" Male NPT, 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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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89
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Save 19% Save %
$ 2.69
$ 2.69 - $ 2.69
$ 2.69
$ 2.19
$ 2.19 - $ 2.19
$ 2.19

Foster 11-3, 3 Series, Industrial Plug, 1/4" Female NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 2.69
$ 2.69 - $ 2.69
$ 2.69
$ 2.19
$ 2.19 - $ 2.19
$ 2.19
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$ 2.89
$ 2.89 - $ 2.89
$ 2.89
$ 2.29
$ 2.29 - $ 2.29
$ 2.29

Foster 12-3, 3 Series, Industrial Plug, 1/8" Male NPT, 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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$ 2.89
$ 2.89 - $ 2.89
$ 2.89
$ 2.29
$ 2.29 - $ 2.29
$ 2.29
Save 21% Save %
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$ 3.39
$ 3.39 - $ 3.39
$ 3.39
$ 2.69
$ 2.69 - $ 2.69
$ 2.69

Foster 16-3, 3 Series, Industrial Plug, 1/4" Hose Barb, 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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$ 3.39
$ 3.39 - $ 3.39
$ 3.39
$ 2.69
$ 2.69 - $ 2.69
$ 2.69
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$ 4.79
$ 4.79 - $ 4.79
$ 4.79
$ 3.79
$ 3.79 - $ 3.79
$ 3.79

Foster 11-3B, 3 Series, Industrial Plug, 1/4" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 4.79
$ 4.79 - $ 4.79
$ 4.79
$ 3.79
$ 3.79 - $ 3.79
$ 3.79
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$ 21.99
$ 21.99 - $ 21.99
$ 21.99
$ 17.59
$ 17.59 - $ 17.59
$ 17.59

Foster FM3103, 3 Series, Industrial Coupler, Automatic, 1/4" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3103 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 21.99
$ 21.99 - $ 21.99
$ 21.99
$ 17.59
$ 17.59 - $ 17.59
$ 17.59
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$ 23.49
$ 23.49 - $ 23.49
$ 23.49
$ 18.79
$ 18.79 - $ 18.79
$ 18.79

Foster 3003GB, 3 Series, Industrial Coupler, Automatic, 1/4" Female NPT, Brass

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

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$ 23.49
$ 23.49 - $ 23.49
$ 23.49
$ 18.79
$ 18.79 - $ 18.79
$ 18.79
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$ 12.99
$ 12.99 - $ 12.99
$ 12.99
$ 10.39
$ 10.39 - $ 10.39
$ 10.39

Foster SG3103, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3103 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 12.99
$ 12.99 - $ 12.99
$ 12.99
$ 10.39
$ 10.39 - $ 10.39
$ 10.39
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$ 5.59
$ 5.59 - $ 5.59
$ 5.59
$ 4.49
$ 4.49 - $ 4.49
$ 4.49

Foster 13-3B, 3 Series, Industrial Plug, 1/8" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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$ 5.59
$ 5.59 - $ 5.59
$ 5.59
$ 4.49
$ 4.49 - $ 4.49
$ 4.49
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$ 7.29
$ 7.29 - $ 7.29
$ 7.29
$ 5.89
$ 5.89 - $ 5.89
$ 5.89

Foster 17-3B, 3 Series, Industrial Plug, 3/8" Hose Barb, 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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$ 7.29
$ 7.29 - $ 7.29
$ 7.29
$ 5.89
$ 5.89 - $ 5.89
$ 5.89
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$ 21.49
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$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19

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

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

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$ 21.49
$ 21.49 - $ 21.49
$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19
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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 2.99
$ 2.99 - $ 2.99
$ 2.99

Foster 17-3, 3 Series, Industrial Plug, 3/8" Hose Barb, 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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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 2.99
$ 2.99 - $ 2.99
$ 2.99
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$ 14.39
$ 14.39 - $ 14.39
$ 14.39
$ 11.49
$ 11.49 - $ 11.49
$ 11.49

Foster 3603, 3 Series, Industrial Coupler, Manual, 1/4" Hose Barb, Brass, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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$ 14.39
$ 14.39 - $ 14.39
$ 14.39
$ 11.49
$ 11.49 - $ 11.49
$ 11.49
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$ 22.19
$ 22.19 - $ 22.19
$ 22.19
$ 17.79
$ 17.79 - $ 17.79
$ 17.79

Foster FM3203, 3 Series, Industrial Coupler, Automatic, 3/8" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3203 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 22.19
$ 22.19 - $ 22.19
$ 22.19
$ 17.79
$ 17.79 - $ 17.79
$ 17.79
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$ 12.89
$ 12.89 - $ 12.89
$ 12.89
$ 10.29
$ 10.29 - $ 10.29
$ 10.29

Foster SG3003, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3003 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

View full details
$ 12.89
$ 12.89 - $ 12.89
$ 12.89
$ 10.29
$ 10.29 - $ 10.29
$ 10.29
Save 20% Save %
Save 20% Save %
$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99

Foster 3303, 3 Series, Industrial Coupler, Manual, 3/8" Male NPT, Brass, Steel

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

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$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99
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Save 20% Save %
$ 15.69
$ 15.69 - $ 15.69
$ 15.69
$ 12.59
$ 12.59 - $ 12.59
$ 12.59

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

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

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$ 15.69
$ 15.69 - $ 15.69
$ 15.69
$ 12.59
$ 12.59 - $ 12.59
$ 12.59
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Save 20% Save %
$ 19.89
$ 19.89 - $ 19.89
$ 19.89
$ 15.89
$ 15.89 - $ 15.89
$ 15.89

Foster 3003HW, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, Brass (HOT WATER)

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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$ 19.89
$ 19.89 - $ 19.89
$ 19.89
$ 15.89
$ 15.89 - $ 15.89
$ 15.89
Save 20% Save %
Save 20% Save %
$ 22.39
$ 22.39 - $ 22.39
$ 22.39
$ 17.89
$ 17.89 - $ 17.89
$ 17.89

Foster FM3303, 3 Series, Industrial Coupler, Automatic, 3/8" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

View full details
$ 22.39
$ 22.39 - $ 22.39
$ 22.39
$ 17.89
$ 17.89 - $ 17.89
$ 17.89
Save 20% Save %
Save 20% Save %
$ 13.49
$ 13.49 - $ 13.49
$ 13.49
$ 10.79
$ 10.79 - $ 10.79
$ 10.79

Foster SG3603, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

View full details
$ 13.49
$ 13.49 - $ 13.49
$ 13.49
$ 10.79
$ 10.79 - $ 10.79
$ 10.79
Save 20% Save %
Save 21% Save %
$ 3.29
$ 3.29 - $ 3.29
$ 3.29
$ 2.59
$ 2.59 - $ 2.59
$ 2.59

Foster 13-3, 3 Series, Industrial Plug, 1/8" Female NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 3.29
$ 3.29 - $ 3.29
$ 3.29
$ 2.59
$ 2.59 - $ 2.59
$ 2.59
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