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Foster ISO-B Series Couplers

Foster ISO-B (FHK) Series hydraulic quick couplers and plugs, compatible with ISO 7241-1 Series B — the most widely used industrial hydraulic interchange. Two-way shut-off seals both halves at disconnect to prevent fluid loss and air inclusion. Manual sleeve connection at zero pressure. Body sizes 1/8" to 1", in RoHS-plated steel, brass, and 303/316 stainless with Buna-N seals.

  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 25.79
    $ 25.79 - $ 25.79
    $ 25.79
    $ 20.59
    $ 20.59 - $ 20.59
    $ 20.59

    Foster K4S-103, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, EPDM Seal, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S-103 is a plated steel 1/2" plug from th...

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    $ 25.79
    $ 25.79 - $ 25.79
    $ 25.79
    $ 20.59
    $ 20.59 - $ 20.59
    $ 20.59
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 71.09
    $ 71.09 - $ 71.09
    $ 71.09
    $ 56.89
    $ 56.89 - $ 56.89
    $ 56.89

    Foster K4S/S, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S/S is a 303 stainless steel 1/2" plug fr...

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    $ 71.09
    $ 71.09 - $ 71.09
    $ 71.09
    $ 56.89
    $ 56.89 - $ 56.89
    $ 56.89
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 76.89
    $ 76.89 - $ 76.89
    $ 76.89
    $ 61.49
    $ 61.49 - $ 61.49
    $ 61.49

    Foster K4S/S-101, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Viton Seal, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S/S-101 is a 303 stainless steel 1/2" plu...

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    $ 76.89
    $ 76.89 - $ 76.89
    $ 76.89
    $ 61.49
    $ 61.49 - $ 61.49
    $ 61.49
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 77.89
    $ 77.89 - $ 77.89
    $ 77.89
    $ 62.29
    $ 62.29 - $ 62.29
    $ 62.29

    Foster K4S/S-103, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, EPDM Seal, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S/S-103 is a 303 stainless steel 1/2" plu...

    View full details
    $ 77.89
    $ 77.89 - $ 77.89
    $ 77.89
    $ 62.29
    $ 62.29 - $ 62.29
    $ 62.29
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 72.49
    $ 72.49 - $ 72.49
    $ 72.49
    $ 57.99
    $ 57.99 - $ 57.99
    $ 57.99

    Foster K4S/SLV, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Less Valve, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S/SLV is a 303 stainless steel 1/2" plug ...

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    $ 72.49
    $ 72.49 - $ 72.49
    $ 72.49
    $ 57.99
    $ 57.99 - $ 57.99
    $ 57.99
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 30.99
    $ 30.99 - $ 30.99
    $ 30.99
    $ 24.79
    $ 24.79 - $ 24.79
    $ 24.79

    Foster K4S10, 1/2" ISO-B Hydraulic Plug x 7/8"-14 SAE, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4S10 is a plated steel 1/2" plug from the ...

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    $ 30.99
    $ 30.99 - $ 30.99
    $ 30.99
    $ 24.79
    $ 24.79 - $ 24.79
    $ 24.79
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 21.49
    $ 21.49 - $ 21.49
    $ 21.49
    $ 17.19
    $ 17.19 - $ 17.19
    $ 17.19

    Foster K4SLV, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Less Valve, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K4SLV is a plated steel 1/2" plug from the ...

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    $ 21.49
    $ 21.49 - $ 21.49
    $ 21.49
    $ 17.19
    $ 17.19 - $ 17.19
    $ 17.19
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 40.49
    $ 40.49 - $ 40.49
    $ 40.49
    $ 32.39
    $ 32.39 - $ 32.39
    $ 32.39

    Foster K6B, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6B is a brass 3/4" plug from the ISO-B Ser...

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    $ 40.49
    $ 40.49 - $ 40.49
    $ 40.49
    $ 32.39
    $ 32.39 - $ 32.39
    $ 32.39
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 52.09
    $ 52.09 - $ 52.09
    $ 52.09
    $ 41.69
    $ 41.69 - $ 41.69
    $ 41.69

    Foster K6B-101, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Viton Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6B-101 is a brass 3/4" plug from the ISO-B...

    View full details
    $ 52.09
    $ 52.09 - $ 52.09
    $ 52.09
    $ 41.69
    $ 41.69 - $ 41.69
    $ 41.69
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 49.29
    $ 49.29 - $ 49.29
    $ 49.29
    $ 39.39
    $ 39.39 - $ 39.39
    $ 39.39

    Foster K6B-103, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, EPDM Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6B-103 is a brass 3/4" plug from the ISO-B...

    View full details
    $ 49.29
    $ 49.29 - $ 49.29
    $ 49.29
    $ 39.39
    $ 39.39 - $ 39.39
    $ 39.39
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 37.39
    $ 37.39 - $ 37.39
    $ 37.39
    $ 29.89
    $ 29.89 - $ 29.89
    $ 29.89

    Foster K6S, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S is a plated steel 3/4" plug from the IS...

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    $ 37.39
    $ 37.39 - $ 37.39
    $ 37.39
    $ 29.89
    $ 29.89 - $ 29.89
    $ 29.89
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 41.09
    $ 41.09 - $ 41.09
    $ 41.09
    $ 32.89
    $ 32.89 - $ 32.89
    $ 32.89

    Foster K6S-101, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Viton Seal, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S-101 is a plated steel 3/4" plug from th...

    View full details
    $ 41.09
    $ 41.09 - $ 41.09
    $ 41.09
    $ 32.89
    $ 32.89 - $ 32.89
    $ 32.89
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 40.29
    $ 40.29 - $ 40.29
    $ 40.29
    $ 32.29
    $ 32.29 - $ 32.29
    $ 32.29

    Foster K6S-102, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Neoprene Seal, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S-102 is a plated steel 3/4" plug from th...

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    $ 40.29
    $ 40.29 - $ 40.29
    $ 40.29
    $ 32.29
    $ 32.29 - $ 32.29
    $ 32.29
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 40.39
    $ 40.39 - $ 40.39
    $ 40.39
    $ 32.29
    $ 32.29 - $ 32.29
    $ 32.29

    Foster K6S-103, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, EPDM Seal, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S-103 is a plated steel 3/4" plug from th...

    View full details
    $ 40.39
    $ 40.39 - $ 40.39
    $ 40.39
    $ 32.29
    $ 32.29 - $ 32.29
    $ 32.29
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 107.09
    $ 107.09 - $ 107.09
    $ 107.09
    $ 85.69
    $ 85.69 - $ 85.69
    $ 85.69

    Foster K6S/S, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S/S is a 303 stainless steel 3/4" plug fr...

    View full details
    $ 107.09
    $ 107.09 - $ 107.09
    $ 107.09
    $ 85.69
    $ 85.69 - $ 85.69
    $ 85.69
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 114.89
    $ 114.89 - $ 114.89
    $ 114.89
    $ 91.89
    $ 91.89 - $ 91.89
    $ 91.89

    Foster K6S/S-101, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Viton Seal, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S/S-101 is a 303 stainless steel 3/4" plu...

    View full details
    $ 114.89
    $ 114.89 - $ 114.89
    $ 114.89
    $ 91.89
    $ 91.89 - $ 91.89
    $ 91.89
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 116.39
    $ 116.39 - $ 116.39
    $ 116.39
    $ 93.19
    $ 93.19 - $ 93.19
    $ 93.19

    Foster K6S/S-103, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, EPDM Seal, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S/S-103 is a 303 stainless steel 3/4" plu...

    View full details
    $ 116.39
    $ 116.39 - $ 116.39
    $ 116.39
    $ 93.19
    $ 93.19 - $ 93.19
    $ 93.19
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 109.19
    $ 109.19 - $ 109.19
    $ 109.19
    $ 87.29
    $ 87.29 - $ 87.29
    $ 87.29

    Foster K6S/SLV, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Less Valve, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S/SLV is a 303 stainless steel 3/4" plug ...

    View full details
    $ 109.19
    $ 109.19 - $ 109.19
    $ 109.19
    $ 87.29
    $ 87.29 - $ 87.29
    $ 87.29
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 41.99
    $ 41.99 - $ 41.99
    $ 41.99
    $ 33.59
    $ 33.59 - $ 33.59
    $ 33.59

    Foster K6S12, 3/4" ISO-B Hydraulic Plug x 1-1/16"-12 SAE, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6S12 is a plated steel 3/4" plug from the ...

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    $ 41.99
    $ 41.99 - $ 41.99
    $ 41.99
    $ 33.59
    $ 33.59 - $ 33.59
    $ 33.59
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 33.69
    $ 33.69 - $ 33.69
    $ 33.69
    $ 26.99
    $ 26.99 - $ 26.99
    $ 26.99

    Foster K6SLV, 3/4" ISO-B Hydraulic Plug x 3/4" Female NPT, ISO-B Series, Less Valve, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K6SLV is a plated steel 3/4" plug from the ...

    View full details
    $ 33.69
    $ 33.69 - $ 33.69
    $ 33.69
    $ 26.99
    $ 26.99 - $ 26.99
    $ 26.99
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 65.29
    $ 65.29 - $ 65.29
    $ 65.29
    $ 52.19
    $ 52.19 - $ 52.19
    $ 52.19

    Foster K8B, 1" ISO-B Hydraulic Plug x 1" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K8B is a brass 1" plug from the ISO-B Serie...

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    $ 65.29
    $ 65.29 - $ 65.29
    $ 65.29
    $ 52.19
    $ 52.19 - $ 52.19
    $ 52.19
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 81.89
    $ 81.89 - $ 81.89
    $ 81.89
    $ 65.49
    $ 65.49 - $ 65.49
    $ 65.49

    Foster K8B-101, 1" ISO-B Hydraulic Plug x 1" Female NPT, ISO-B Series, Viton Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K8B-101 is a brass 1" plug from the ISO-B S...

    View full details
    $ 81.89
    $ 81.89 - $ 81.89
    $ 81.89
    $ 65.49
    $ 65.49 - $ 65.49
    $ 65.49
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 80.69
    $ 80.69 - $ 80.69
    $ 80.69
    $ 64.49
    $ 64.49 - $ 64.49
    $ 64.49

    Foster K8B-103, 1" ISO-B Hydraulic Plug x 1" Female NPT, ISO-B Series, EPDM Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K8B-103 is a brass 1" plug from the ISO-B S...

    View full details
    $ 80.69
    $ 80.69 - $ 80.69
    $ 80.69
    $ 64.49
    $ 64.49 - $ 64.49
    $ 64.49
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 49.49
    $ 49.49 - $ 49.49
    $ 49.49
    $ 39.59
    $ 39.59 - $ 39.59
    $ 39.59

    Foster K8S, 1" ISO-B Hydraulic Plug x 1" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K8S is a plated steel 1" plug from the ISO-...

    View full details
    $ 49.49
    $ 49.49 - $ 49.49
    $ 49.49
    $ 39.59
    $ 39.59 - $ 39.59
    $ 39.59
    Save 20% Save %