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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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$ 46.00
$ 46.00 - $ 46.00
$ 46.00
$ 36.00
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$ 36.00

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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$ 46.00
$ 46.00 - $ 46.00
$ 46.00
$ 36.00
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$ 36.00
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$ 284.00
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$ 284.00
$ 227.00
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$ 227.00

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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$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 227.00
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$ 227.00
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$ 72.00
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$ 72.00
$ 59.00
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$ 59.00

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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$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 59.00
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$ 59.00
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$ 257.00
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$ 257.00
$ 206.00
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$ 206.00

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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$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
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$ 206.00
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$ 51.00
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$ 51.00
$ 42.00
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$ 42.00

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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$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 42.00
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$ 42.00
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$ 55.00
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$ 55.00
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$ 44.00

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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$ 55.00
$ 55.00 - $ 55.00
$ 55.00
$ 44.00
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$ 44.00
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$ 65.00
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$ 65.00
$ 51.00
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$ 51.00

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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$ 65.00
$ 65.00 - $ 65.00
$ 65.00
$ 51.00
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$ 51.00
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$ 91.00
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$ 91.00
$ 72.00
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$ 72.00

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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$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
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$ 72.00
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$ 416.00
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$ 416.00
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$ 333.00

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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$ 416.00
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$ 416.00
$ 333.00
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$ 333.00
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$ 444.00
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$ 444.00
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$ 356.00

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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$ 444.00
$ 444.00 - $ 444.00
$ 444.00
$ 356.00
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$ 356.00
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$ 106.00
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$ 106.00
$ 85.00
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$ 85.00

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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$ 106.00
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$ 106.00
$ 85.00
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$ 85.00
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$ 272.00
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$ 272.00
$ 218.00
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$ 218.00

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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$ 272.00
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$ 272.00
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$ 218.00
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$ 246.00
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$ 246.00
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$ 197.00

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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$ 246.00
$ 246.00 - $ 246.00
$ 246.00
$ 197.00
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$ 197.00
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$ 72.00
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$ 72.00
$ 57.00
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$ 57.00

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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$ 72.00
$ 72.00 - $ 72.00
$ 72.00
$ 57.00
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$ 57.00
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$ 138.00
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$ 138.00
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$ 112.00

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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$ 138.00
$ 138.00 - $ 138.00
$ 138.00
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$ 112.00
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$ 407.00
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$ 407.00
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$ 325.00

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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$ 407.00
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$ 407.00
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$ 325.00
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$ 420.00
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$ 337.00

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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$ 420.00
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$ 420.00
$ 337.00
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$ 337.00
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$ 244.00
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$ 195.00

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...

View full details
$ 244.00
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$ 244.00
$ 195.00
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$ 195.00
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$ 284.00
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$ 284.00
$ 227.00
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$ 227.00

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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$ 284.00
$ 284.00 - $ 284.00
$ 284.00
$ 227.00
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$ 227.00
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$ 297.00
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$ 297.00
$ 238.00
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$ 238.00

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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$ 297.00
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$ 297.00
$ 238.00
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$ 238.00
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$ 376.00
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$ 376.00
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$ 301.00

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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$ 376.00
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$ 376.00
$ 301.00
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$ 301.00
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$ 424.00
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$ 424.00
$ 338.00
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$ 338.00

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...

View full details
$ 424.00
$ 424.00 - $ 424.00
$ 424.00
$ 338.00
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$ 338.00
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$ 255.00
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$ 255.00
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$ 204.00

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...

View full details
$ 255.00
$ 255.00 - $ 255.00
$ 255.00
$ 204.00
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$ 204.00
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$ 63.00
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$ 63.00
$ 49.00
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$ 49.00

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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$ 63.00
$ 63.00 - $ 63.00
$ 63.00
$ 49.00
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$ 49.00
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