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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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$ 8.49
$ 8.49 - $ 8.49
$ 8.49
$ 6.79
$ 6.79 - $ 6.79
$ 6.79

Foster 165-3, 3 Series, Industrial Plug, 5/16" Hose Barb, 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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$ 8.49
$ 8.49 - $ 8.49
$ 8.49
$ 6.79
$ 6.79 - $ 6.79
$ 6.79
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$ 22.59
$ 22.59 - $ 22.59
$ 22.59
$ 18.09
$ 18.09 - $ 18.09
$ 18.09

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

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603GS 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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$ 15.09
$ 15.09 - $ 15.09
$ 15.09
$ 12.09
$ 12.09 - $ 12.09
$ 12.09

Foster SG1713, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 3/8" Push-On Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG1713 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 15.09
$ 15.09 - $ 15.09
$ 15.09
$ 12.09
$ 12.09 - $ 12.09
$ 12.09
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$ 4.59
$ 4.59 - $ 4.59
$ 4.59
$ 3.69
$ 3.69 - $ 3.69
$ 3.69

Foster 71-3, 3 Series, Industrial Plug, 3/8" Hose Barb (Push-On), 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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$ 4.59
$ 4.59 - $ 4.59
$ 4.59
$ 3.69
$ 3.69 - $ 3.69
$ 3.69
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$ 65.89
$ 65.89 - $ 65.89
$ 65.89
$ 52.69
$ 52.69 - $ 52.69
$ 52.69

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

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 65.89
$ 65.89 - $ 65.89
$ 65.89
$ 52.69
$ 52.69 - $ 52.69
$ 52.69
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$ 29.19
$ 29.19 - $ 29.19
$ 29.19
$ 23.39
$ 23.39 - $ 23.39
$ 23.39

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

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

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$ 29.19
$ 29.19 - $ 29.19
$ 29.19
$ 23.39
$ 23.39 - $ 23.39
$ 23.39
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$ 22.69
$ 22.69 - $ 22.69
$ 22.69
$ 18.19
$ 18.19 - $ 18.19
$ 18.19

Foster SL3003, 3 Series, Industrial Coupler, Automatic, 1/4" Female NPT, Brass With Ball Sleeve Lock

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SL3003 is a Brass 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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$ 7.99
$ 7.99 - $ 7.99
$ 7.99
$ 6.39
$ 6.39 - $ 6.39
$ 6.39

Foster 16-3B, 3 Series, Industrial Plug, 1/4" Hose Barb, 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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$ 7.99
$ 7.99 - $ 7.99
$ 7.99
$ 6.39
$ 6.39 - $ 6.39
$ 6.39
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$ 13.89
$ 13.89 - $ 13.89
$ 13.89
$ 11.09
$ 11.09 - $ 11.09
$ 11.09

Foster SG3203, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 3/8" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3203 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 13.89
$ 13.89 - $ 13.89
$ 13.89
$ 11.09
$ 11.09 - $ 11.09
$ 11.09
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$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.19
$ 11.19 - $ 11.19
$ 11.19

Foster SG3303, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 3/8" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.19
$ 11.19 - $ 11.19
$ 11.19
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$ 44.29
$ 44.29 - $ 44.29
$ 44.29
$ 35.39
$ 35.39 - $ 35.39
$ 35.39

Foster 3003S/S, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, Stainless Steel

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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$ 44.29
$ 44.29 - $ 44.29
$ 44.29
$ 35.39
$ 35.39 - $ 35.39
$ 35.39
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$ 4.99
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$ 4.99
$ 3.99
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$ 3.99

Foster 12-3B, 3 Series, Industrial Plug, 1/8" Male NPT, 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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$ 4.99
$ 4.99 - $ 4.99
$ 4.99
$ 3.99
$ 3.99 - $ 3.99
$ 3.99
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$ 26.69
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$ 26.69
$ 21.39
$ 21.39 - $ 21.39
$ 21.39

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

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

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$ 26.69
$ 26.69 - $ 26.69
$ 26.69
$ 21.39
$ 21.39 - $ 21.39
$ 21.39
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$ 29.69
$ 29.69 - $ 29.69
$ 29.69
$ 23.69
$ 23.69 - $ 23.69
$ 23.69

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

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

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$ 29.69
$ 29.69 - $ 29.69
$ 29.69
$ 23.69
$ 23.69 - $ 23.69
$ 23.69
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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 2.99
$ 2.99 - $ 2.99
$ 2.99

Foster 14-3, 3 Series, Industrial Plug, 3/8" Male NPT, 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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$ 3.79
$ 3.79 - $ 3.79
$ 3.79
$ 2.99
$ 2.99 - $ 2.99
$ 2.99
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$ 15.19
$ 15.19 - $ 15.19
$ 15.19
$ 12.19
$ 12.19 - $ 12.19
$ 12.19

Foster 3203, 3 Series, Industrial Coupler, Manual, 3/8" Female NPT, 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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$ 15.19
$ 15.19 - $ 15.19
$ 15.19
$ 12.19
$ 12.19 - $ 12.19
$ 12.19
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$ 5.79
$ 5.79 - $ 5.79
$ 5.79
$ 4.59
$ 4.59 - $ 4.59
$ 4.59

Foster 15-3, 3 Series, Industrial Plug, 3/8" Female NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 15-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 5.79
$ 5.79 - $ 5.79
$ 5.79
$ 4.59
$ 4.59 - $ 4.59
$ 4.59
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$ 22.79
$ 22.79 - $ 22.79
$ 22.79
$ 18.29
$ 18.29 - $ 18.29
$ 18.29

Foster FM3603, 3 Series, Industrial Coupler, Automatic, 1/4" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 22.79
$ 22.79 - $ 22.79
$ 22.79
$ 18.29
$ 18.29 - $ 18.29
$ 18.29
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$ 23.59
$ 23.59 - $ 23.59
$ 23.59
$ 18.89
$ 18.89 - $ 18.89
$ 18.89

Foster FM3703, 3 Series, Industrial Coupler, Automatic, 3/8" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3703 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 23.59
$ 23.59 - $ 23.59
$ 23.59
$ 18.89
$ 18.89 - $ 18.89
$ 18.89
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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89

Foster SG3703, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 3/8" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3703 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 13.59
$ 13.59 - $ 13.59
$ 13.59
$ 10.89
$ 10.89 - $ 10.89
$ 10.89
Save 20% Save %
Save 20% Save %
$ 16.19
$ 16.19 - $ 16.19
$ 16.19
$ 12.89
$ 12.89 - $ 12.89
$ 12.89

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

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
Save 20% Save %
Save 20% Save %
$ 9.39
$ 9.39 - $ 9.39
$ 9.39
$ 7.49
$ 7.49 - $ 7.49
$ 7.49

Foster 14-3B, 3 Series, Industrial Plug, 3/8" Male NPT, 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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$ 9.39
$ 9.39 - $ 9.39
$ 9.39
$ 7.49
$ 7.49 - $ 7.49
$ 7.49
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Save 21% Save %
$ 5.19
$ 5.19 - $ 5.19
$ 5.19
$ 4.09
$ 4.09 - $ 4.09
$ 4.09

Foster 51-3, 3 Series, Industrial Plug, 1/4" Hose Barb (Push-On), 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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$ 5.19
$ 5.19 - $ 5.19
$ 5.19
$ 4.09
$ 4.09 - $ 4.09
$ 4.09
Save 21% Save %
Save 20% Save %
$ 12.49
$ 12.49 - $ 12.49
$ 12.49
$ 9.99
$ 9.99 - $ 9.99
$ 9.99

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

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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$ 12.49
$ 12.49 - $ 12.49
$ 12.49
$ 9.99
$ 9.99 - $ 9.99
$ 9.99
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