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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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    $ 29.29
    $ 29.29 - $ 29.29
    $ 29.29
    $ 23.39
    $ 23.39 - $ 23.39
    $ 23.39

    Foster H2S6, 1/4" ISO-B Hydraulic Coupler x 9/16"-18 SAE, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H2S6 is a plated steel 1/4" coupler from th...

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    $ 29.29
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    $ 29.29
    $ 23.39
    $ 23.39 - $ 23.39
    $ 23.39
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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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    $ 37.79
    $ 37.79 - $ 37.79
    $ 37.79
    $ 30.29
    $ 30.29 - $ 30.29
    $ 30.29

    Foster H3B, 3/8" ISO-B Hydraulic Coupler x 3/8" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3B is a brass 3/8" coupler from the ISO-B ...

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    $ 37.79
    $ 37.79 - $ 37.79
    $ 37.79
    $ 30.29
    $ 30.29 - $ 30.29
    $ 30.29
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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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    $ 44.69
    $ 44.69 - $ 44.69
    $ 44.69
    $ 35.69
    $ 35.69 - $ 35.69
    $ 35.69

    Foster H3B-101, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3B-101 is a brass 3/8" coupler from the IS...

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    $ 44.69
    $ 44.69 - $ 44.69
    $ 44.69
    $ 35.69
    $ 35.69 - $ 35.69
    $ 35.69
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
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    $ 45.39
    $ 45.39 - $ 45.39
    $ 45.39
    $ 36.39
    $ 36.39 - $ 36.39
    $ 36.39

    Foster H3B-102, 3/8" ISO-B Hydraulic Coupler x 3/8" Female NPT, ISO-B Series, Neoprene Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3B-102 is a brass 3/8" coupler from the IS...

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    $ 45.39
    $ 45.39 - $ 45.39
    $ 45.39
    $ 36.39
    $ 36.39 - $ 36.39
    $ 36.39
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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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    $ 43.49
    $ 43.49 - $ 43.49
    $ 43.49
    $ 34.79
    $ 34.79 - $ 34.79
    $ 34.79

    Foster H3B-103, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3B-103 is a brass 3/8" coupler from the IS...

    View full details
    $ 43.49
    $ 43.49 - $ 43.49
    $ 43.49
    $ 34.79
    $ 34.79 - $ 34.79
    $ 34.79
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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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    $ 46.29
    $ 46.29 - $ 46.29
    $ 46.29
    $ 36.99
    $ 36.99 - $ 36.99
    $ 36.99

    Foster H3B-104, 3/8" ISO-B Hydraulic Coupler x 3/8" Female NPT, ISO-B Series, Silicone Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3B-104 is a brass 3/8" coupler from the IS...

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    $ 46.29
    $ 46.29 - $ 46.29
    $ 46.29
    $ 36.99
    $ 36.99 - $ 36.99
    $ 36.99
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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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    $ 38.79
    $ 38.79 - $ 38.79
    $ 38.79
    $ 31.09
    $ 31.09 - $ 31.09
    $ 31.09

    Foster H3S, 3/8" ISO-B Hydraulic Coupler x 3/8" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3S is a plated steel 3/8" coupler from the...

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    $ 38.79
    $ 38.79 - $ 38.79
    $ 38.79
    $ 31.09
    $ 31.09 - $ 31.09
    $ 31.09
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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 %
    $ 44.59
    $ 44.59 - $ 44.59
    $ 44.59
    $ 35.69
    $ 35.69 - $ 35.69
    $ 35.69

    Foster H3S-101, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3S-101 is a plated steel 3/8" coupler from...

    View full details
    $ 44.59
    $ 44.59 - $ 44.59
    $ 44.59
    $ 35.69
    $ 35.69 - $ 35.69
    $ 35.69
    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 %
    $ 45.09
    $ 45.09 - $ 45.09
    $ 45.09
    $ 36.09
    $ 36.09 - $ 36.09
    $ 36.09

    Foster H3S-102, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3S-102 is a plated steel 3/8" coupler from...

    View full details
    $ 45.09
    $ 45.09 - $ 45.09
    $ 45.09
    $ 36.09
    $ 36.09 - $ 36.09
    $ 36.09
    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 %
    $ 43.39
    $ 43.39 - $ 43.39
    $ 43.39
    $ 34.69
    $ 34.69 - $ 34.69
    $ 34.69

    Foster H3S-103, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3S-103 is a plated steel 3/8" coupler from...

    View full details
    $ 43.39
    $ 43.39 - $ 43.39
    $ 43.39
    $ 34.69
    $ 34.69 - $ 34.69
    $ 34.69
    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 %
    $ 45.39
    $ 45.39 - $ 45.39
    $ 45.39
    $ 36.39
    $ 36.39 - $ 36.39
    $ 36.39

    Foster H3S-104, 3/8" ISO-B Hydraulic Coupler x 3/8" Female NPT, ISO-B Series, Silicone Seal, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3S-104 is a plated steel 3/8" coupler from...

    View full details
    $ 45.39
    $ 45.39 - $ 45.39
    $ 45.39
    $ 36.39
    $ 36.39 - $ 36.39
    $ 36.39
    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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    $ 90.09
    $ 90.09 - $ 90.09
    $ 90.09
    $ 72.09
    $ 72.09 - $ 72.09
    $ 72.09

    Foster H3S/S, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3S/S is a 303 stainless steel 3/8" coupler...

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    $ 90.09
    $ 90.09 - $ 90.09
    $ 90.09
    $ 72.09
    $ 72.09 - $ 72.09
    $ 72.09
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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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    $ 95.49
    $ 95.49 - $ 95.49
    $ 95.49
    $ 76.39
    $ 76.39 - $ 76.39
    $ 76.39

    Foster H3S/S-101, 3/8" ISO-B Hydraulic Coupler x 3/8" 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 H3S/S-101 is a 303 stainless steel 3/8" cou...

    View full details
    $ 95.49
    $ 95.49 - $ 95.49
    $ 95.49
    $ 76.39
    $ 76.39 - $ 76.39
    $ 76.39
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 44.89
    $ 44.89 - $ 44.89
    $ 44.89
    $ 35.89
    $ 35.89 - $ 35.89
    $ 35.89

    Foster H3S8, 3/8" ISO-B Hydraulic Coupler x 3/4"-16 SAE, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H3S8 is a plated steel 3/8" coupler from th...

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    $ 44.89
    $ 44.89 - $ 44.89
    $ 44.89
    $ 35.89
    $ 35.89 - $ 35.89
    $ 35.89
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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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    $ 63.79
    $ 63.79 - $ 63.79
    $ 63.79
    $ 50.99
    $ 50.99 - $ 50.99
    $ 50.99

    Foster H4B, 1/2" ISO-B Hydraulic Coupler x 1/2" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H4B is a brass 1/2" coupler from the ISO-B ...

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    $ 63.79
    $ 63.79 - $ 63.79
    $ 63.79
    $ 50.99
    $ 50.99 - $ 50.99
    $ 50.99
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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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    $ 76.19
    $ 76.19 - $ 76.19
    $ 76.19
    $ 60.99
    $ 60.99 - $ 60.99
    $ 60.99

    Foster H4B-101, 1/2" ISO-B Hydraulic Coupler x 1/2" 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 H4B-101 is a brass 1/2" coupler from the IS...

    View full details
    $ 76.19
    $ 76.19 - $ 76.19
    $ 76.19
    $ 60.99
    $ 60.99 - $ 60.99
    $ 60.99
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  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 71.49
    $ 71.49 - $ 71.49
    $ 71.49
    $ 57.19
    $ 57.19 - $ 57.19
    $ 57.19

    Foster H4B-102, 1/2" ISO-B Hydraulic Coupler x 1/2" Female NPT, ISO-B Series, Neoprene Seal, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H4B-102 is a brass 1/2" coupler from the IS...

    View full details
    $ 71.49
    $ 71.49 - $ 71.49
    $ 71.49
    $ 57.19
    $ 57.19 - $ 57.19
    $ 57.19
    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 %
    $ 72.29
    $ 72.29 - $ 72.29
    $ 72.29
    $ 57.89
    $ 57.89 - $ 57.89
    $ 57.89

    Foster H4B-103, 1/2" ISO-B Hydraulic Coupler x 1/2" 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 H4B-103 is a brass 1/2" coupler from the IS...

    View full details
    $ 72.29
    $ 72.29 - $ 72.29
    $ 72.29
    $ 57.89
    $ 57.89 - $ 57.89
    $ 57.89
    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 %
    $ 49.99
    $ 49.99 - $ 49.99
    $ 49.99
    $ 39.99
    $ 39.99 - $ 39.99
    $ 39.99

    Foster H4S, 1/2" ISO-B Hydraulic Coupler x 1/2" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster H4S is a plated steel 1/2" coupler from the...

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    $ 49.99
    $ 49.99 - $ 49.99
    $ 49.99
    $ 39.99
    $ 39.99 - $ 39.99
    $ 39.99
    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 %
    $ 57.99
    $ 57.99 - $ 57.99
    $ 57.99
    $ 46.39
    $ 46.39 - $ 46.39
    $ 46.39

    Foster H4S-101, 1/2" ISO-B Hydraulic Coupler x 1/2" 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 H4S-101 is a plated steel 1/2" coupler from...

    View full details
    $ 57.99
    $ 57.99 - $ 57.99
    $ 57.99
    $ 46.39
    $ 46.39 - $ 46.39
    $ 46.39
    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 %
    $ 55.99
    $ 55.99 - $ 55.99
    $ 55.99
    $ 44.79
    $ 44.79 - $ 44.79
    $ 44.79

    Foster H4S-103, 1/2" ISO-B Hydraulic Coupler 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 H4S-103 is a plated steel 1/2" coupler from...

    View full details
    $ 55.99
    $ 55.99 - $ 55.99
    $ 55.99
    $ 44.79
    $ 44.79 - $ 44.79
    $ 44.79
    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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    $ 158.49
    $ 158.49 - $ 158.49
    $ 158.49
    $ 126.79
    $ 126.79 - $ 126.79
    $ 126.79

    Foster H4S/S, 1/2" ISO-B Hydraulic Coupler 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 H4S/S is a 303 stainless steel 1/2" coupler...

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    $ 158.49
    $ 158.49 - $ 158.49
    $ 158.49
    $ 126.79
    $ 126.79 - $ 126.79
    $ 126.79
    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 %
    $ 164.29
    $ 164.29 - $ 164.29
    $ 164.29
    $ 131.39
    $ 131.39 - $ 131.39
    $ 131.39

    Foster H4S/S-101, 1/2" ISO-B Hydraulic Coupler 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 H4S/S-101 is a 303 stainless steel 1/2" cou...

    View full details
    $ 164.29
    $ 164.29 - $ 164.29
    $ 164.29
    $ 131.39
    $ 131.39 - $ 131.39
    $ 131.39
    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 %
    $ 166.59
    $ 166.59 - $ 166.59
    $ 166.59
    $ 133.29
    $ 133.29 - $ 133.29
    $ 133.29

    Foster H4S/S-103, 1/2" ISO-B Hydraulic Coupler 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 H4S/S-103 is a 303 stainless steel 1/2" cou...

    View full details
    $ 166.59
    $ 166.59 - $ 166.59
    $ 166.59
    $ 133.29
    $ 133.29 - $ 133.29
    $ 133.29
    Save 20% Save %