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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 $ 12.29
    Original price $ 12.29 - Original price $ 12.29
    Original price $ 12.29
    Current price $ 9.79
    $ 9.79 - $ 9.79
    Current price $ 9.79

    Foster 75FP, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FP is a steel 3/4" plug from the FST Straight-Thru Series - with NO valve i...

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    Original price $ 12.29
    Original price $ 12.29 - Original price $ 12.29
    Original price $ 12.29
    Current price $ 9.79
    $ 9.79 - $ 9.79
    Current price $ 9.79
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  • Original price $ 15.29
    Original price $ 15.29 - Original price $ 15.29
    Original price $ 15.29
    Current price $ 12.29
    $ 12.29 - $ 12.29
    Current price $ 12.29

    Foster 75FPB, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FPB is a brass 3/4" plug from the FST Straight-Thru Series - with NO valve ...

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    Original price $ 15.29
    Original price $ 15.29 - Original price $ 15.29
    Original price $ 15.29
    Current price $ 12.29
    $ 12.29 - $ 12.29
    Current price $ 12.29
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  • Original price $ 49.19
    Original price $ 49.19 - Original price $ 49.19
    Original price $ 49.19
    Current price $ 39.29
    $ 39.29 - $ 39.29
    Current price $ 39.29

    Foster 75FPS, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FPS is a 303 stainless steel 3/4" plug from the FST Straight-Thru Series - ...

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    Original price $ 49.19
    Original price $ 49.19 - Original price $ 49.19
    Original price $ 49.19
    Current price $ 39.29
    $ 39.29 - $ 39.29
    Current price $ 39.29
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  • Original price $ 35.59
    Original price $ 35.59 - Original price $ 35.59
    Original price $ 35.59
    Current price $ 28.49
    $ 28.49 - $ 28.49
    Current price $ 28.49

    Foster 75FS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FS is a brass 3/4" coupler from the FST Straight-Thru Series - with NO valv...

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    Original price $ 35.59
    Original price $ 35.59 - Original price $ 35.59
    Original price $ 35.59
    Current price $ 28.49
    $ 28.49 - $ 28.49
    Current price $ 28.49
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  • Original price $ 40.39
    Original price $ 40.39 - Original price $ 40.39
    Original price $ 40.39
    Current price $ 32.29
    $ 32.29 - $ 32.29
    Current price $ 32.29

    Foster 75FS-101, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Viton Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FS-101 is a brass 3/4" coupler from the FST Straight-Thru Series - with NO ...

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    Original price $ 40.39
    Original price $ 40.39 - Original price $ 40.39
    Original price $ 40.39
    Current price $ 32.29
    $ 32.29 - $ 32.29
    Current price $ 32.29
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  • Original price $ 39.69
    Original price $ 39.69 - Original price $ 39.69
    Original price $ 39.69
    Current price $ 31.79
    $ 31.79 - $ 31.79
    Current price $ 31.79

    Foster 75FS-103, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, EPDM Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FS-103 is a brass 3/4" coupler from the FST Straight-Thru Series - with NO ...

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    Original price $ 39.69
    Original price $ 39.69 - Original price $ 39.69
    Original price $ 39.69
    Current price $ 31.79
    $ 31.79 - $ 31.79
    Current price $ 31.79
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  • Original price $ 41.29
    Original price $ 41.29 - Original price $ 41.29
    Original price $ 41.29
    Current price $ 33.09
    $ 33.09 - $ 33.09
    Current price $ 33.09

    Foster 75FS-104, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Silicone Seal, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FS-104 is a brass 3/4" coupler from the FST Straight-Thru Series - with NO ...

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    Original price $ 41.29
    Original price $ 41.29 - Original price $ 41.29
    Original price $ 41.29
    Current price $ 33.09
    $ 33.09 - $ 33.09
    Current price $ 33.09
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  • Original price $ 116.99
    Original price $ 116.99 - Original price $ 116.99
    Original price $ 116.99
    Current price $ 93.59
    $ 93.59 - $ 93.59
    Current price $ 93.59

    Foster 75FSS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FSS is a 303 stainless steel 3/4" coupler from the FST Straight-Thru Series...

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    Original price $ 116.99
    Original price $ 116.99 - Original price $ 116.99
    Original price $ 116.99
    Current price $ 93.59
    $ 93.59 - $ 93.59
    Current price $ 93.59
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  • Original price $ 120.69
    Original price $ 120.69 - Original price $ 120.69
    Original price $ 120.69
    Current price $ 96.49
    $ 96.49 - $ 96.49
    Current price $ 96.49

    Foster 75FSS-101, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Viton Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FSS-101 is a 303 stainless steel 3/4" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 120.69
    Original price $ 120.69 - Original price $ 120.69
    Original price $ 120.69
    Current price $ 96.49
    $ 96.49 - $ 96.49
    Current price $ 96.49
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  • Original price $ 122.49
    Original price $ 122.49 - Original price $ 122.49
    Original price $ 122.49
    Current price $ 97.99
    $ 97.99 - $ 97.99
    Current price $ 97.99

    Foster 75FSS-103, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, EPDM Seal, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75FSS-103 is a 303 stainless steel 3/4" coupler from the FST Straight-Thru Se...

    View full details
    Original price $ 122.49
    Original price $ 122.49 - Original price $ 122.49
    Original price $ 122.49
    Current price $ 97.99
    $ 97.99 - $ 97.99
    Current price $ 97.99
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  • Original price $ 17.39
    Original price $ 17.39 - Original price $ 17.39
    Original price $ 17.39
    Current price $ 13.89
    $ 13.89 - $ 13.89
    Current price $ 13.89

    Foster 75HPB, 3/4" Straight-Thru Plug x 3/4" Hose ID, FST Series, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster 75HPB is a brass 3/4" plug from the FST Straight-Thru Series - with NO valve ...

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    Original price $ 17.39
    Original price $ 17.39 - Original price $ 17.39
    Original price $ 17.39
    Current price $ 13.89
    $ 13.89 - $ 13.89
    Current price $ 13.89
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  • Original price $ 64.79
    Original price $ 64.79 - Original price $ 64.79
    Original price $ 64.79
    Current price $ 51.79
    $ 51.79 - $ 51.79
    Current price $ 51.79

    Foster BL100FS, 1" Straight-Thru Coupler x 1" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL100FS is a brass 1" coupler from the FST Straight-Thru Series - with NO val...

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    Original price $ 64.79
    Original price $ 64.79 - Original price $ 64.79
    Original price $ 64.79
    Current price $ 51.79
    $ 51.79 - $ 51.79
    Current price $ 51.79
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  • Original price $ 188.79
    Original price $ 188.79 - Original price $ 188.79
    Original price $ 188.79
    Current price $ 150.99
    $ 150.99 - $ 150.99
    Current price $ 150.99

    Foster BL100FSS, 1" Straight-Thru Coupler x 1" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL100FSS is a 303 stainless steel 1" coupler from the FST Straight-Thru Serie...

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    Original price $ 188.79
    Original price $ 188.79 - Original price $ 188.79
    Original price $ 188.79
    Current price $ 150.99
    $ 150.99 - $ 150.99
    Current price $ 150.99
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  • Original price $ 173.59
    Original price $ 173.59 - Original price $ 173.59
    Original price $ 173.59
    Current price $ 138.89
    $ 138.89 - $ 138.89
    Current price $ 138.89

    Foster BL125FS, 1-1/4" Straight-Thru Coupler x 1-1/4" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL125FS is a brass 1-1/4" coupler from the FST Straight-Thru Series - with NO...

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    Original price $ 173.59
    Original price $ 173.59 - Original price $ 173.59
    Original price $ 173.59
    Current price $ 138.89
    $ 138.89 - $ 138.89
    Current price $ 138.89
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  • Original price $ 18.49
    Original price $ 18.49 - Original price $ 18.49
    Original price $ 18.49
    Current price $ 14.79
    $ 14.79 - $ 14.79
    Current price $ 14.79

    Foster BL12FS, 1/8" Straight-Thru Coupler x 1/8" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL12FS is a brass 1/8" coupler from the FST Straight-Thru Series - with NO va...

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    Original price $ 18.49
    Original price $ 18.49 - Original price $ 18.49
    Original price $ 18.49
    Current price $ 14.79
    $ 14.79 - $ 14.79
    Current price $ 14.79
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  • Original price $ 47.79
    Original price $ 47.79 - Original price $ 47.79
    Original price $ 47.79
    Current price $ 38.19
    $ 38.19 - $ 38.19
    Current price $ 38.19

    Foster BL12FSS, 1/8" Straight-Thru Coupler x 1/8" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL12FSS is a 303 stainless steel 1/8" coupler from the FST Straight-Thru Seri...

    View full details
    Original price $ 47.79
    Original price $ 47.79 - Original price $ 47.79
    Original price $ 47.79
    Current price $ 38.19
    $ 38.19 - $ 38.19
    Current price $ 38.19
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  • Original price $ 301.29
    Original price $ 301.29 - Original price $ 301.29
    Original price $ 301.29
    Current price $ 240.99
    $ 240.99 - $ 240.99
    Current price $ 240.99

    Foster BL150FS, 1-1/2" Straight-Thru Coupler x 1-1/2" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL150FS is a brass 1-1/2" coupler from the FST Straight-Thru Series - with NO...

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    Original price $ 301.29
    Original price $ 301.29 - Original price $ 301.29
    Original price $ 301.29
    Current price $ 240.99
    $ 240.99 - $ 240.99
    Current price $ 240.99
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  • Original price $ 20.59
    Original price $ 20.59 - Original price $ 20.59
    Original price $ 20.59
    Current price $ 16.49
    $ 16.49 - $ 16.49
    Current price $ 16.49

    Foster BL25FS, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL25FS is a brass 1/4" coupler from the FST Straight-Thru Series - with NO va...

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    Original price $ 20.59
    Original price $ 20.59 - Original price $ 20.59
    Original price $ 20.59
    Current price $ 16.49
    $ 16.49 - $ 16.49
    Current price $ 16.49
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  • Original price $ 73.49
    Original price $ 73.49 - Original price $ 73.49
    Original price $ 73.49
    Current price $ 58.79
    $ 58.79 - $ 58.79
    Current price $ 58.79

    Foster BL25FSS, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL25FSS is a 303 stainless steel 1/4" coupler from the FST Straight-Thru Seri...

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    Original price $ 73.49
    Original price $ 73.49 - Original price $ 73.49
    Original price $ 73.49
    Current price $ 58.79
    $ 58.79 - $ 58.79
    Current price $ 58.79
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  • Original price $ 23.89
    Original price $ 23.89 - Original price $ 23.89
    Original price $ 23.89
    Current price $ 19.09
    $ 19.09 - $ 19.09
    Current price $ 19.09

    Foster BL38FS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL38FS is a brass 3/8" coupler from the FST Straight-Thru Series - with NO va...

    View full details
    Original price $ 23.89
    Original price $ 23.89 - Original price $ 23.89
    Original price $ 23.89
    Current price $ 19.09
    $ 19.09 - $ 19.09
    Current price $ 19.09
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  • Original price $ 79.19
    Original price $ 79.19 - Original price $ 79.19
    Original price $ 79.19
    Current price $ 63.29
    $ 63.29 - $ 63.29
    Current price $ 63.29

    Foster BL38FSS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL38FSS is a 303 stainless steel 3/8" coupler from the FST Straight-Thru Seri...

    View full details
    Original price $ 79.19
    Original price $ 79.19 - Original price $ 79.19
    Original price $ 79.19
    Current price $ 63.29
    $ 63.29 - $ 63.29
    Current price $ 63.29
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  • Original price $ 30.89
    Original price $ 30.89 - Original price $ 30.89
    Original price $ 30.89
    Current price $ 24.69
    $ 24.69 - $ 24.69
    Current price $ 24.69

    Foster BL50FS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL50FS is a brass 1/2" coupler from the FST Straight-Thru Series - with NO va...

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    Original price $ 30.89
    Original price $ 30.89 - Original price $ 30.89
    Original price $ 30.89
    Current price $ 24.69
    $ 24.69 - $ 24.69
    Current price $ 24.69
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  • Original price $ 89.49
    Original price $ 89.49 - Original price $ 89.49
    Original price $ 89.49
    Current price $ 71.59
    $ 71.59 - $ 71.59
    Current price $ 71.59

    Foster BL50FSS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL50FSS is a 303 stainless steel 1/2" coupler from the FST Straight-Thru Seri...

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    Original price $ 89.49
    Original price $ 89.49 - Original price $ 89.49
    Original price $ 89.49
    Current price $ 71.59
    $ 71.59 - $ 71.59
    Current price $ 71.59
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  • Original price $ 46.89
    Original price $ 46.89 - Original price $ 46.89
    Original price $ 46.89
    Current price $ 37.49
    $ 37.49 - $ 37.49
    Current price $ 37.49

    Foster BL75FS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Ball Lock, Brass

    In stock

    Maximum-flow connections for air, fluid, and vacuum lines. The Foster BL75FS is a brass 3/4" coupler from the FST Straight-Thru Series - with NO va...

    View full details
    Original price $ 46.89
    Original price $ 46.89 - Original price $ 46.89
    Original price $ 46.89
    Current price $ 37.49
    $ 37.49 - $ 37.49
    Current price $ 37.49
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