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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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$ 161.00
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$ 161.00
$ 129.00
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$ 129.00

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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$ 161.00
$ 161.00 - $ 161.00
$ 161.00
$ 129.00
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$ 129.00
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$ 427.00
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$ 427.00
$ 342.00
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$ 342.00

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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$ 427.00
$ 427.00 - $ 427.00
$ 427.00
$ 342.00
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$ 342.00
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$ 151.00
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$ 151.00
$ 121.00
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$ 121.00

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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$ 151.00
$ 151.00 - $ 151.00
$ 151.00
$ 121.00
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$ 121.00
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$ 286.00
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$ 286.00
$ 229.00
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$ 229.00

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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$ 286.00
$ 286.00 - $ 286.00
$ 286.00
$ 229.00
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$ 229.00
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$ 99.00
$ 99.00 - $ 99.00
$ 99.00
$ 78.00
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$ 78.00

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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$ 99.00
$ 99.00 - $ 99.00
$ 99.00
$ 78.00
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$ 78.00
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$ 87.00
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$ 87.00
$ 70.00
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$ 70.00

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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$ 87.00
$ 87.00 - $ 87.00
$ 87.00
$ 70.00
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$ 70.00
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$ 1,245.00
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$ 1,245.00
$ 996.00
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$ 996.00

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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$ 1,245.00
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$ 1,245.00
$ 996.00
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$ 996.00
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$ 552.00
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$ 552.00
$ 442.00
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$ 442.00

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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$ 552.00
$ 552.00 - $ 552.00
$ 552.00
$ 442.00
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$ 442.00
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$ 429.00
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$ 429.00
$ 344.00
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$ 344.00

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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$ 429.00
$ 429.00 - $ 429.00
$ 429.00
$ 344.00
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$ 344.00
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$ 263.00
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$ 263.00
$ 210.00
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$ 210.00

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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$ 263.00
$ 263.00 - $ 263.00
$ 263.00
$ 210.00
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$ 210.00
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$ 267.00
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$ 267.00
$ 212.00
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$ 212.00

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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$ 267.00
$ 267.00 - $ 267.00
$ 267.00
$ 212.00
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$ 212.00
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$ 837.00
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$ 837.00
$ 669.00
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$ 669.00

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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$ 837.00
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$ 837.00
$ 669.00
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$ 669.00
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$ 95.00
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$ 95.00
$ 76.00
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$ 76.00

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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$ 95.00
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$ 95.00
$ 76.00
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$ 76.00
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$ 505.00
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$ 505.00
$ 405.00
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$ 405.00

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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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
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$ 405.00
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$ 561.00
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$ 561.00
$ 448.00
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$ 448.00

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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$ 561.00
$ 561.00 - $ 561.00
$ 561.00
$ 448.00
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$ 448.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 327.00
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$ 327.00
$ 263.00
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$ 263.00

Foster 10-3DB, 1/4" Industrial Plug x 1/4" Male NPT, 3 Series, Dill Valve, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3DB is a Brass 1/4" industrial plug from the Foster 3 Series — the most...

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$ 327.00
$ 327.00 - $ 327.00
$ 327.00
$ 263.00
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$ 263.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 301.00
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$ 301.00

Foster SB3-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB3-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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$ 374.00
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$ 374.00
$ 301.00
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$ 301.00
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$ 72.00
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$ 72.00
$ 57.00
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$ 57.00

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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$ 72.00
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$ 72.00
$ 57.00
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$ 57.00
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$ 287.00
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$ 287.00
$ 231.00
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$ 231.00

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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$ 287.00
$ 287.00 - $ 287.00
$ 287.00
$ 231.00
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$ 231.00
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$ 110.00
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$ 110.00
$ 87.00
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$ 87.00

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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$ 110.00
$ 110.00 - $ 110.00
$ 110.00
$ 87.00
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$ 87.00
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$ 431.00
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$ 431.00
$ 346.00
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$ 346.00

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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$ 431.00
$ 431.00 - $ 431.00
$ 431.00
$ 346.00
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$ 346.00
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$ 446.00
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$ 446.00
$ 357.00
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$ 357.00

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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$ 446.00
$ 446.00 - $ 446.00
$ 446.00
$ 357.00
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$ 357.00
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$ 257.00
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$ 257.00
$ 206.00
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$ 206.00

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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$ 257.00
$ 257.00 - $ 257.00
$ 257.00
$ 206.00
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$ 206.00
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$ 306.00
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$ 306.00
$ 244.00
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$ 244.00

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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$ 306.00
$ 306.00 - $ 306.00
$ 306.00
$ 244.00
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$ 244.00
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