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Foster FST Series Couplers (Straight-Thru)

Foster FST Series full-flow straight-through hydraulic couplers and plugs — no valve in either half, so the inside diameter matches the nominal pipe for maximum flow. Standard Industrial Interchange with manual sleeve connection, body sizes 1/8" to 1-1/2". Brass, steel, and 303 stainless; ball-lock option available. Note: lines do not self-seal on disconnect.

  • Original price $ 16.29
    Original price $ 16.29 - Original price $ 16.29
    Original price $ 16.29
    Current price $ 12.99
    $ 12.99 - $ 12.99
    Current price $ 12.99

    Foster 25FS-101, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Viton Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 25FS-101 is a brass 1/4" coupler from the FST Straight-Thru Series - with NO ...

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    Original price $ 16.29
    Original price $ 16.29 - Original price $ 16.29
    Original price $ 16.29
    Current price $ 12.99
    $ 12.99 - $ 12.99
    Current price $ 12.99
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  • Original price $ 64.49
    Original price $ 64.49 - Original price $ 64.49
    Original price $ 64.49
    Current price $ 51.59
    $ 51.59 - $ 51.59
    Current price $ 51.59

    Foster 25FSS, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 25FSS is a 303 stainless steel 1/4" coupler from the FST Straight-Thru Series...

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    Original price $ 64.49
    Original price $ 64.49 - Original price $ 64.49
    Original price $ 64.49
    Current price $ 51.59
    $ 51.59 - $ 51.59
    Current price $ 51.59
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  • Original price $ 67.79
    Original price $ 67.79 - Original price $ 67.79
    Original price $ 67.79
    Current price $ 54.29
    $ 54.29 - $ 54.29
    Current price $ 54.29

    Foster 25FSS-101, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Viton Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 25FSS-101 is a 303 stainless steel 1/4" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 67.79
    Original price $ 67.79 - Original price $ 67.79
    Original price $ 67.79
    Current price $ 54.29
    $ 54.29 - $ 54.29
    Current price $ 54.29
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  • Original price $ 67.49
    Original price $ 67.49 - Original price $ 67.49
    Original price $ 67.49
    Current price $ 53.99
    $ 53.99 - $ 53.99
    Current price $ 53.99

    Foster 25FSS-103, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, EPDM Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 25FSS-103 is a 303 stainless steel 1/4" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 67.49
    Original price $ 67.49 - Original price $ 67.49
    Original price $ 67.49
    Current price $ 53.99
    $ 53.99 - $ 53.99
    Current price $ 53.99
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  • Original price $ 8.89
    Original price $ 8.89 - Original price $ 8.89
    Original price $ 8.89
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09

    Foster 25HP, 1/4" Straight-Thru Plug x 1/4" Hose ID, FST Series, Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 25HP is a steel 1/4" plug from the FST Straight-Thru Series - with NO valve i...

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    Original price $ 8.89
    Original price $ 8.89 - Original price $ 8.89
    Original price $ 8.89
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09
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  • Original price $ 5.69
    Original price $ 5.69 - Original price $ 5.69
    Original price $ 5.69
    Current price $ 4.49
    $ 4.49 - $ 4.49
    Current price $ 4.49

    Foster 38FP, 3/8" Straight-Thru Plug x 3/8" Female NPT, FST Series, Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FP is a steel 3/8" plug from the FST Straight-Thru Series - with NO valve i...

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    Original price $ 5.69
    Original price $ 5.69 - Original price $ 5.69
    Original price $ 5.69
    Current price $ 4.49
    $ 4.49 - $ 4.49
    Current price $ 4.49
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  • Original price $ 7.09
    Original price $ 7.09 - Original price $ 7.09
    Original price $ 7.09
    Current price $ 5.59
    $ 5.59 - $ 5.59
    Current price $ 5.59

    Foster 38FPB, 3/8" Straight-Thru Plug x 3/8" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FPB is a brass 3/8" plug from the FST Straight-Thru Series - with NO valve ...

    View full details
    Original price $ 7.09
    Original price $ 7.09 - Original price $ 7.09
    Original price $ 7.09
    Current price $ 5.59
    $ 5.59 - $ 5.59
    Current price $ 5.59
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  • Original price $ 26.19
    Original price $ 26.19 - Original price $ 26.19
    Original price $ 26.19
    Current price $ 20.99
    $ 20.99 - $ 20.99
    Current price $ 20.99

    Foster 38FPS, 3/8" Straight-Thru Plug x 3/8" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FPS is a 303 stainless steel 3/8" plug from the FST Straight-Thru Series - ...

    View full details
    Original price $ 26.19
    Original price $ 26.19 - Original price $ 26.19
    Original price $ 26.19
    Current price $ 20.99
    $ 20.99 - $ 20.99
    Current price $ 20.99
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  • Original price $ 15.79
    Original price $ 15.79 - Original price $ 15.79
    Original price $ 15.79
    Current price $ 12.69
    $ 12.69 - $ 12.69
    Current price $ 12.69

    Foster 38FS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FS is a brass 3/8" coupler from the FST Straight-Thru Series - with NO valv...

    View full details
    Original price $ 15.79
    Original price $ 15.79 - Original price $ 15.79
    Original price $ 15.79
    Current price $ 12.69
    $ 12.69 - $ 12.69
    Current price $ 12.69
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  • Original price $ 19.19
    Original price $ 19.19 - Original price $ 19.19
    Original price $ 19.19
    Current price $ 15.29
    $ 15.29 - $ 15.29
    Current price $ 15.29

    Foster 38FS-101, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Viton Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FS-101 is a brass 3/8" coupler from the FST Straight-Thru Series - with NO ...

    View full details
    Original price $ 19.19
    Original price $ 19.19 - Original price $ 19.19
    Original price $ 19.19
    Current price $ 15.29
    $ 15.29 - $ 15.29
    Current price $ 15.29
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  • Original price $ 18.39
    Original price $ 18.39 - Original price $ 18.39
    Original price $ 18.39
    Current price $ 14.69
    $ 14.69 - $ 14.69
    Current price $ 14.69

    Foster 38FS-103, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, EPDM Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FS-103 is a brass 3/8" coupler from the FST Straight-Thru Series - with NO ...

    View full details
    Original price $ 18.39
    Original price $ 18.39 - Original price $ 18.39
    Original price $ 18.39
    Current price $ 14.69
    $ 14.69 - $ 14.69
    Current price $ 14.69
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  • Original price $ 70.79
    Original price $ 70.79 - Original price $ 70.79
    Original price $ 70.79
    Current price $ 56.59
    $ 56.59 - $ 56.59
    Current price $ 56.59

    Foster 38FSS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FSS is a 303 stainless steel 3/8" coupler from the FST Straight-Thru Series...

    View full details
    Original price $ 70.79
    Original price $ 70.79 - Original price $ 70.79
    Original price $ 70.79
    Current price $ 56.59
    $ 56.59 - $ 56.59
    Current price $ 56.59
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  • Original price $ 71.29
    Original price $ 71.29 - Original price $ 71.29
    Original price $ 71.29
    Current price $ 56.99
    $ 56.99 - $ 56.99
    Current price $ 56.99

    Foster 38FSS-101, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Viton Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FSS-101 is a 303 stainless steel 3/8" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 71.29
    Original price $ 71.29 - Original price $ 71.29
    Original price $ 71.29
    Current price $ 56.99
    $ 56.99 - $ 56.99
    Current price $ 56.99
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  • Original price $ 70.89
    Original price $ 70.89 - Original price $ 70.89
    Original price $ 70.89
    Current price $ 56.69
    $ 56.69 - $ 56.69
    Current price $ 56.69

    Foster 38FSS-103, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, EPDM Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38FSS-103 is a 303 stainless steel 3/8" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 70.89
    Original price $ 70.89 - Original price $ 70.89
    Original price $ 70.89
    Current price $ 56.69
    $ 56.69 - $ 56.69
    Current price $ 56.69
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  • Original price $ 8.79
    Original price $ 8.79 - Original price $ 8.79
    Original price $ 8.79
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09

    Foster 38HPB, 3/8" Straight-Thru Plug x 3/8" Hose ID, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 38HPB is a brass 3/8" plug from the FST Straight-Thru Series - with NO valve ...

    View full details
    Original price $ 8.79
    Original price $ 8.79 - Original price $ 8.79
    Original price $ 8.79
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09
    Save 19% Save %
  • Original price $ 8.89
    Original price $ 8.89 - Original price $ 8.89
    Original price $ 8.89
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09

    Foster 50FP, 1/2" Straight-Thru Plug x 1/2" Female NPT, FST Series, Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FP is a steel 1/2" plug from the FST Straight-Thru Series - with NO valve i...

    View full details
    Original price $ 8.89
    Original price $ 8.89 - Original price $ 8.89
    Original price $ 8.89
    Current price $ 7.09
    $ 7.09 - $ 7.09
    Current price $ 7.09
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  • Original price $ 8.29
    Original price $ 8.29 - Original price $ 8.29
    Original price $ 8.29
    Current price $ 6.59
    $ 6.59 - $ 6.59
    Current price $ 6.59

    Foster 50FPB, 1/2" Straight-Thru Plug x 1/2" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FPB is a brass 1/2" plug from the FST Straight-Thru Series - with NO valve ...

    View full details
    Original price $ 8.29
    Original price $ 8.29 - Original price $ 8.29
    Original price $ 8.29
    Current price $ 6.59
    $ 6.59 - $ 6.59
    Current price $ 6.59
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  • Original price $ 35.29
    Original price $ 35.29 - Original price $ 35.29
    Original price $ 35.29
    Current price $ 28.19
    $ 28.19 - $ 28.19
    Current price $ 28.19

    Foster 50FPS, 1/2" Straight-Thru Plug x 1/2" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FPS is a 303 stainless steel 1/2" plug from the FST Straight-Thru Series - ...

    View full details
    Original price $ 35.29
    Original price $ 35.29 - Original price $ 35.29
    Original price $ 35.29
    Current price $ 28.19
    $ 28.19 - $ 28.19
    Current price $ 28.19
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  • Original price $ 22.19
    Original price $ 22.19 - Original price $ 22.19
    Original price $ 22.19
    Current price $ 17.79
    $ 17.79 - $ 17.79
    Current price $ 17.79

    Foster 50FS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FS is a brass 1/2" coupler from the FST Straight-Thru Series - with NO valv...

    View full details
    Original price $ 22.19
    Original price $ 22.19 - Original price $ 22.19
    Original price $ 22.19
    Current price $ 17.79
    $ 17.79 - $ 17.79
    Current price $ 17.79
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  • Original price $ 25.19
    Original price $ 25.19 - Original price $ 25.19
    Original price $ 25.19
    Current price $ 20.19
    $ 20.19 - $ 20.19
    Current price $ 20.19

    Foster 50FS-101, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Viton Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FS-101 is a brass 1/2" coupler from the FST Straight-Thru Series - with NO ...

    View full details
    Original price $ 25.19
    Original price $ 25.19 - Original price $ 25.19
    Original price $ 25.19
    Current price $ 20.19
    $ 20.19 - $ 20.19
    Current price $ 20.19
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  • Original price $ 24.79
    Original price $ 24.79 - Original price $ 24.79
    Original price $ 24.79
    Current price $ 19.89
    $ 19.89 - $ 19.89
    Current price $ 19.89

    Foster 50FS-103, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, EPDM Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FS-103 is a brass 1/2" coupler from the FST Straight-Thru Series - with NO ...

    View full details
    Original price $ 24.79
    Original price $ 24.79 - Original price $ 24.79
    Original price $ 24.79
    Current price $ 19.89
    $ 19.89 - $ 19.89
    Current price $ 19.89
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  • Original price $ 77.99
    Original price $ 77.99 - Original price $ 77.99
    Original price $ 77.99
    Current price $ 62.39
    $ 62.39 - $ 62.39
    Current price $ 62.39

    Foster 50FSS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FSS is a 303 stainless steel 1/2" coupler from the FST Straight-Thru Series...

    View full details
    Original price $ 77.99
    Original price $ 77.99 - Original price $ 77.99
    Original price $ 77.99
    Current price $ 62.39
    $ 62.39 - $ 62.39
    Current price $ 62.39
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  • Original price $ 80.79
    Original price $ 80.79 - Original price $ 80.79
    Original price $ 80.79
    Current price $ 64.69
    $ 64.69 - $ 64.69
    Current price $ 64.69

    Foster 50FSS-101, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Viton Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FSS-101 is a 303 stainless steel 1/2" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 80.79
    Original price $ 80.79 - Original price $ 80.79
    Original price $ 80.79
    Current price $ 64.69
    $ 64.69 - $ 64.69
    Current price $ 64.69
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  • Original price $ 82.19
    Original price $ 82.19 - Original price $ 82.19
    Original price $ 82.19
    Current price $ 65.79
    $ 65.79 - $ 65.79
    Current price $ 65.79

    Foster 50FSS-103, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, EPDM Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 50FSS-103 is a 303 stainless steel 1/2" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 82.19
    Original price $ 82.19 - Original price $ 82.19
    Original price $ 82.19
    Current price $ 65.79
    $ 65.79 - $ 65.79
    Current price $ 65.79
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