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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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$ 42.00
$ 42.00 - $ 42.00
$ 42.00
$ 33.00
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$ 33.00

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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$ 42.00
$ 42.00 - $ 42.00
$ 42.00
$ 33.00
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$ 33.00
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$ 261.00
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$ 261.00
$ 209.00
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$ 209.00

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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$ 261.00
$ 261.00 - $ 261.00
$ 261.00
$ 209.00
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$ 209.00
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$ 66.00
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$ 66.00
$ 54.00
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$ 54.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 54.00
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$ 54.00
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$ 237.00
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$ 237.00
$ 190.00
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$ 190.00

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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$ 237.00
$ 237.00 - $ 237.00
$ 237.00
$ 190.00
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$ 190.00
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$ 47.00
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$ 47.00
$ 39.00
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$ 39.00

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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$ 47.00
$ 47.00 - $ 47.00
$ 47.00
$ 39.00
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$ 39.00
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$ 51.00
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$ 51.00
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$ 40.00

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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$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 40.00
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$ 40.00
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$ 59.00
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$ 59.00
$ 47.00
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$ 47.00

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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$ 59.00
$ 59.00 - $ 59.00
$ 59.00
$ 47.00
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$ 47.00
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$ 84.00
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$ 84.00
$ 66.00
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$ 66.00

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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$ 84.00
$ 84.00 - $ 84.00
$ 84.00
$ 66.00
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$ 66.00
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$ 383.00
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$ 383.00
$ 306.00
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$ 306.00

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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$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
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$ 306.00
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$ 409.00
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$ 409.00
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$ 327.00

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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$ 409.00
$ 409.00 - $ 409.00
$ 409.00
$ 327.00
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$ 327.00
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$ 226.00
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$ 226.00
$ 181.00
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$ 181.00

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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$ 226.00
$ 226.00 - $ 226.00
$ 226.00
$ 181.00
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$ 181.00
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$ 98.00
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$ 98.00
$ 79.00
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$ 79.00

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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$ 98.00
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$ 98.00
$ 79.00
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$ 79.00
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$ 127.00
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$ 127.00
$ 103.00
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$ 103.00

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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$ 127.00
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$ 127.00
$ 103.00
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$ 103.00
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$ 374.00
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$ 374.00
$ 300.00
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$ 300.00

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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$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 300.00
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$ 300.00
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$ 66.00
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$ 66.00
$ 53.00
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$ 53.00

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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$ 66.00
$ 66.00 - $ 66.00
$ 66.00
$ 53.00
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$ 53.00
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$ 251.00
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$ 251.00
$ 200.00
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$ 200.00

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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$ 251.00
$ 251.00 - $ 251.00
$ 251.00
$ 200.00
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$ 200.00
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$ 387.00
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$ 387.00
$ 310.00
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$ 310.00

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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$ 387.00
$ 387.00 - $ 387.00
$ 387.00
$ 310.00
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$ 310.00
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$ 225.00
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$ 225.00
$ 180.00
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$ 180.00

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...

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$ 225.00
$ 225.00 - $ 225.00
$ 225.00
$ 180.00
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$ 180.00
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$ 261.00
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$ 261.00
$ 209.00
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$ 209.00

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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$ 261.00
$ 261.00 - $ 261.00
$ 261.00
$ 209.00
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$ 209.00
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$ 273.00
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$ 273.00
$ 220.00
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$ 220.00

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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$ 273.00
$ 273.00 - $ 273.00
$ 273.00
$ 220.00
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$ 220.00
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$ 347.00
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$ 347.00
$ 277.00
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$ 277.00

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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$ 347.00
$ 347.00 - $ 347.00
$ 347.00
$ 277.00
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$ 277.00
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$ 390.00
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$ 390.00
$ 312.00
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$ 312.00

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...

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$ 390.00
$ 390.00 - $ 390.00
$ 390.00
$ 312.00
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$ 312.00
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$ 235.00
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$ 235.00
$ 188.00
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$ 188.00

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...

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$ 235.00
$ 235.00 - $ 235.00
$ 235.00
$ 188.00
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$ 188.00
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$ 58.00
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$ 58.00
$ 46.00
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$ 46.00

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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$ 58.00
$ 58.00 - $ 58.00
$ 58.00
$ 46.00
$ 46.00 - $ 46.00
$ 46.00
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