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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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$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00

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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$ 148.00
$ 148.00 - $ 148.00
$ 148.00
$ 119.00
$ 119.00 - $ 119.00
$ 119.00
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$ 393.00
$ 393.00 - $ 393.00
$ 393.00
$ 315.00
$ 315.00 - $ 315.00
$ 315.00

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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$ 393.00
$ 393.00 - $ 393.00
$ 393.00
$ 315.00
$ 315.00 - $ 315.00
$ 315.00
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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 211.00
$ 211.00 - $ 211.00
$ 211.00

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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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 211.00
$ 211.00 - $ 211.00
$ 211.00
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$ 80.00
$ 80.00 - $ 80.00
$ 80.00
$ 65.00
$ 65.00 - $ 65.00
$ 65.00

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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$ 80.00
$ 80.00 - $ 80.00
$ 80.00
$ 65.00
$ 65.00 - $ 65.00
$ 65.00
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$ 1,147.00
$ 1,147.00 - $ 1,147.00
$ 1,147.00
$ 917.00
$ 917.00 - $ 917.00
$ 917.00

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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$ 1,147.00
$ 1,147.00 - $ 1,147.00
$ 1,147.00
$ 917.00
$ 917.00 - $ 917.00
$ 917.00
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$ 508.00
$ 508.00 - $ 508.00
$ 508.00
$ 407.00
$ 407.00 - $ 407.00
$ 407.00

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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$ 508.00
$ 508.00 - $ 508.00
$ 508.00
$ 407.00
$ 407.00 - $ 407.00
$ 407.00
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$ 395.00
$ 395.00 - $ 395.00
$ 395.00
$ 317.00
$ 317.00 - $ 317.00
$ 317.00

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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$ 395.00
$ 395.00 - $ 395.00
$ 395.00
$ 317.00
$ 317.00 - $ 317.00
$ 317.00
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$ 139.00
$ 139.00 - $ 139.00
$ 139.00
$ 112.00
$ 112.00 - $ 112.00
$ 112.00

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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$ 139.00
$ 139.00 - $ 139.00
$ 139.00
$ 112.00
$ 112.00 - $ 112.00
$ 112.00
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$ 242.00
$ 242.00 - $ 242.00
$ 242.00
$ 193.00
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$ 193.00

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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$ 242.00
$ 242.00 - $ 242.00
$ 242.00
$ 193.00
$ 193.00 - $ 193.00
$ 193.00
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$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00

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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$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 195.00
$ 195.00 - $ 195.00
$ 195.00
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$ 771.00
$ 771.00 - $ 771.00
$ 771.00
$ 616.00
$ 616.00 - $ 616.00
$ 616.00

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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$ 771.00
$ 771.00 - $ 771.00
$ 771.00
$ 616.00
$ 616.00 - $ 616.00
$ 616.00
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$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
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$ 70.00

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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$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
$ 70.00 - $ 70.00
$ 70.00
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$ 465.00
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$ 465.00
$ 373.00
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$ 373.00

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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$ 465.00
$ 465.00 - $ 465.00
$ 465.00
$ 373.00
$ 373.00 - $ 373.00
$ 373.00
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$ 517.00
$ 517.00 - $ 517.00
$ 517.00
$ 413.00
$ 413.00 - $ 413.00
$ 413.00

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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$ 517.00
$ 517.00 - $ 517.00
$ 517.00
$ 413.00
$ 413.00 - $ 413.00
$ 413.00
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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
$ 53.00 - $ 53.00
$ 53.00
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$ 265.00
$ 265.00 - $ 265.00
$ 265.00
$ 213.00
$ 213.00 - $ 213.00
$ 213.00

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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$ 265.00
$ 265.00 - $ 265.00
$ 265.00
$ 213.00
$ 213.00 - $ 213.00
$ 213.00
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$ 101.00
$ 101.00 - $ 101.00
$ 101.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00

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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$ 101.00
$ 101.00 - $ 101.00
$ 101.00
$ 80.00
$ 80.00 - $ 80.00
$ 80.00
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$ 397.00
$ 397.00 - $ 397.00
$ 397.00
$ 319.00
$ 319.00 - $ 319.00
$ 319.00

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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$ 397.00
$ 397.00 - $ 397.00
$ 397.00
$ 319.00
$ 319.00 - $ 319.00
$ 319.00
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$ 411.00
$ 411.00 - $ 411.00
$ 411.00
$ 329.00
$ 329.00 - $ 329.00
$ 329.00

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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$ 411.00
$ 411.00 - $ 411.00
$ 411.00
$ 329.00
$ 329.00 - $ 329.00
$ 329.00
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$ 237.00
$ 237.00 - $ 237.00
$ 237.00
$ 190.00
$ 190.00 - $ 190.00
$ 190.00

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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$ 237.00
$ 237.00 - $ 237.00
$ 237.00
$ 190.00
$ 190.00 - $ 190.00
$ 190.00
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$ 282.00
$ 282.00 - $ 282.00
$ 282.00
$ 225.00
$ 225.00 - $ 225.00
$ 225.00

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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$ 282.00
$ 282.00 - $ 282.00
$ 282.00
$ 225.00
$ 225.00 - $ 225.00
$ 225.00
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$ 164.00
$ 164.00 - $ 164.00
$ 164.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00

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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$ 164.00
$ 164.00 - $ 164.00
$ 164.00
$ 131.00
$ 131.00 - $ 131.00
$ 131.00
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$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00

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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$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
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$ 218.00
$ 218.00 - $ 218.00
$ 218.00
$ 174.00
$ 174.00 - $ 174.00
$ 174.00

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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$ 218.00
$ 218.00 - $ 218.00
$ 218.00
$ 174.00
$ 174.00 - $ 174.00
$ 174.00
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