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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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    $ 110.39
    $ 110.39 - $ 110.39
    $ 110.39
    $ 88.29
    $ 88.29 - $ 88.29
    $ 88.29

    Foster H8SLV, 1" ISO-B Hydraulic Coupler x 1" 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 H8SLV is a plated steel 1" coupler from the...

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    $ 110.39
    $ 110.39 - $ 110.39
    $ 110.39
    $ 88.29
    $ 88.29 - $ 88.29
    $ 88.29
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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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    $ 9.59
    $ 9.59 - $ 9.59
    $ 9.59
    $ 7.69
    $ 7.69 - $ 7.69
    $ 7.69

    Foster K1B, 1/8" ISO-B Hydraulic Plug x 1/8" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K1B is a brass 1/8" plug from the ISO-B Ser...

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    $ 9.59
    $ 9.59 - $ 9.59
    $ 9.59
    $ 7.69
    $ 7.69 - $ 7.69
    $ 7.69
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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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    $ 14.09
    $ 14.09 - $ 14.09
    $ 14.09
    $ 11.29
    $ 11.29 - $ 11.29
    $ 11.29

    Foster K1B-101, 1/8" ISO-B Hydraulic Plug x 1/8" 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 K1B-101 is a brass 1/8" plug from the ISO-B...

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    $ 14.09
    $ 14.09 - $ 14.09
    $ 14.09
    $ 11.29
    $ 11.29 - $ 11.29
    $ 11.29
    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 %
    $ 13.29
    $ 13.29 - $ 13.29
    $ 13.29
    $ 10.69
    $ 10.69 - $ 10.69
    $ 10.69

    Foster K1B-103, 1/8" ISO-B Hydraulic Plug x 1/8" 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 K1B-103 is a brass 1/8" plug from the ISO-B...

    View full details
    $ 13.29
    $ 13.29 - $ 13.29
    $ 13.29
    $ 10.69
    $ 10.69 - $ 10.69
    $ 10.69
    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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    $ 10.59
    $ 10.59 - $ 10.59
    $ 10.59
    $ 8.49
    $ 8.49 - $ 8.49
    $ 8.49

    Foster K1BLV, 1/8" ISO-B Hydraulic Plug x 1/8" Female NPT, ISO-B Series, Less Valve, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K1BLV is a brass 1/8" plug from the ISO-B S...

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    $ 10.59
    $ 10.59 - $ 10.59
    $ 10.59
    $ 8.49
    $ 8.49 - $ 8.49
    $ 8.49
    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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    $ 8.49
    $ 8.49 - $ 8.49
    $ 8.49
    $ 6.79
    $ 6.79 - $ 6.79
    $ 6.79

    Foster K1S, 1/8" ISO-B Hydraulic Plug x 1/8" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K1S is a plated steel 1/8" plug from the IS...

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    $ 8.49
    $ 8.49 - $ 8.49
    $ 8.49
    $ 6.79
    $ 6.79 - $ 6.79
    $ 6.79
    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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    $ 11.99
    $ 11.99 - $ 11.99
    $ 11.99
    $ 9.59
    $ 9.59 - $ 9.59
    $ 9.59

    Foster K1S-101, 1/8" ISO-B Hydraulic Plug x 1/8" 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 K1S-101 is a plated steel 1/8" plug from th...

    View full details
    $ 11.99
    $ 11.99 - $ 11.99
    $ 11.99
    $ 9.59
    $ 9.59 - $ 9.59
    $ 9.59
    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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    $ 25.59
    $ 25.59 - $ 25.59
    $ 25.59
    $ 20.49
    $ 20.49 - $ 20.49
    $ 20.49

    Foster K1S/S, 1/8" ISO-B Hydraulic Plug x 1/8" 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 K1S/S is a 303 stainless steel 1/8" plug fr...

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    $ 25.59
    $ 25.59 - $ 25.59
    $ 25.59
    $ 20.49
    $ 20.49 - $ 20.49
    $ 20.49
    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 %
    $ 28.59
    $ 28.59 - $ 28.59
    $ 28.59
    $ 22.89
    $ 22.89 - $ 22.89
    $ 22.89

    Foster K1S/S-101, 1/8" ISO-B Hydraulic Plug x 1/8" 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 K1S/S-101 is a 303 stainless steel 1/8" plu...

    View full details
    $ 28.59
    $ 28.59 - $ 28.59
    $ 28.59
    $ 22.89
    $ 22.89 - $ 22.89
    $ 22.89
    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 %
    $ 9.99
    $ 9.99 - $ 9.99
    $ 9.99
    $ 7.99
    $ 7.99 - $ 7.99
    $ 7.99

    Foster K1S4, 1/8" ISO-B Hydraulic Plug x 7/16"-20 SAE, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K1S4 is a plated steel 1/8" plug from the I...

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    $ 9.99
    $ 9.99 - $ 9.99
    $ 9.99
    $ 7.99
    $ 7.99 - $ 7.99
    $ 7.99
    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 %
    $ 13.09
    $ 13.09 - $ 13.09
    $ 13.09
    $ 10.49
    $ 10.49 - $ 10.49
    $ 10.49

    Foster K2B, 1/4" ISO-B Hydraulic Plug x 1/4" Female NPT, ISO-B Series, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K2B is a brass 1/4" plug from the ISO-B Ser...

    View full details
    $ 13.09
    $ 13.09 - $ 13.09
    $ 13.09
    $ 10.49
    $ 10.49 - $ 10.49
    $ 10.49
    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 %
    $ 17.69
    $ 17.69 - $ 17.69
    $ 17.69
    $ 14.19
    $ 14.19 - $ 14.19
    $ 14.19

    Foster K2B-101, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2B-101 is a brass 1/4" plug from the ISO-B...

    View full details
    $ 17.69
    $ 17.69 - $ 17.69
    $ 17.69
    $ 14.19
    $ 14.19 - $ 14.19
    $ 14.19
    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 %
    $ 17.69
    $ 17.69 - $ 17.69
    $ 17.69
    $ 14.09
    $ 14.09 - $ 14.09
    $ 14.09

    Foster K2B-102, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2B-102 is a brass 1/4" plug from the ISO-B...

    View full details
    $ 17.69
    $ 17.69 - $ 17.69
    $ 17.69
    $ 14.09
    $ 14.09 - $ 14.09
    $ 14.09
    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 %
    $ 16.89
    $ 16.89 - $ 16.89
    $ 16.89
    $ 13.49
    $ 13.49 - $ 13.49
    $ 13.49

    Foster K2B-103, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2B-103 is a brass 1/4" plug from the ISO-B...

    View full details
    $ 16.89
    $ 16.89 - $ 16.89
    $ 16.89
    $ 13.49
    $ 13.49 - $ 13.49
    $ 13.49
    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 %
    $ 18.29
    $ 18.29 - $ 18.29
    $ 18.29
    $ 14.69
    $ 14.69 - $ 14.69
    $ 14.69

    Foster K2B-104, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2B-104 is a brass 1/4" plug from the ISO-B...

    View full details
    $ 18.29
    $ 18.29 - $ 18.29
    $ 18.29
    $ 14.69
    $ 14.69 - $ 14.69
    $ 14.69
    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 %
    $ 13.79
    $ 13.79 - $ 13.79
    $ 13.79
    $ 11.09
    $ 11.09 - $ 11.09
    $ 11.09

    Foster K2BLV, 1/4" ISO-B Hydraulic Plug x 1/4" Female NPT, ISO-B Series, Less Valve, Brass

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K2BLV is a brass 1/4" plug from the ISO-B S...

    View full details
    $ 13.79
    $ 13.79 - $ 13.79
    $ 13.79
    $ 11.09
    $ 11.09 - $ 11.09
    $ 11.09
    Save 20% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 19% Save %
    $ 11.29
    $ 11.29 - $ 11.29
    $ 11.29
    $ 9.09
    $ 9.09 - $ 9.09
    $ 9.09

    Foster K2S, 1/4" ISO-B Hydraulic Plug x 1/4" Female NPT, ISO-B Series, Plated Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K2S is a plated steel 1/4" plug from the IS...

    View full details
    $ 11.29
    $ 11.29 - $ 11.29
    $ 11.29
    $ 9.09
    $ 9.09 - $ 9.09
    $ 9.09
    Save 19% Save %
  • Foster FHS4M4B-103, 1/2" Snap-Tite H Interchange Coupler x 1/2" Male NPT, FH Series, EPDM Seal, Brass
    Save 20% Save %
    $ 14.69
    $ 14.69 - $ 14.69
    $ 14.69
    $ 11.79
    $ 11.79 - $ 11.79
    $ 11.79

    Foster K2S-101, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S-101 is a plated steel 1/4" plug from th...

    View full details
    $ 14.69
    $ 14.69 - $ 14.69
    $ 14.69
    $ 11.79
    $ 11.79 - $ 11.79
    $ 11.79
    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 %
    $ 14.49
    $ 14.49 - $ 14.49
    $ 14.49
    $ 11.59
    $ 11.59 - $ 11.59
    $ 11.59

    Foster K2S-103, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S-103 is a plated steel 1/4" plug from th...

    View full details
    $ 14.49
    $ 14.49 - $ 14.49
    $ 14.49
    $ 11.59
    $ 11.59 - $ 11.59
    $ 11.59
    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 %
    $ 14.89
    $ 14.89 - $ 14.89
    $ 14.89
    $ 11.89
    $ 11.89 - $ 11.89
    $ 11.89

    Foster K2S-104, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S-104 is a plated steel 1/4" plug from th...

    View full details
    $ 14.89
    $ 14.89 - $ 14.89
    $ 14.89
    $ 11.89
    $ 11.89 - $ 11.89
    $ 11.89
    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 %
    $ 24.99
    $ 24.99 - $ 24.99
    $ 24.99
    $ 19.99
    $ 19.99 - $ 19.99
    $ 19.99

    Foster K2S/S, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S/S is a 303 stainless steel 1/4" plug fr...

    View full details
    $ 24.99
    $ 24.99 - $ 24.99
    $ 24.99
    $ 19.99
    $ 19.99 - $ 19.99
    $ 19.99
    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 %
    $ 28.59
    $ 28.59 - $ 28.59
    $ 28.59
    $ 22.89
    $ 22.89 - $ 22.89
    $ 22.89

    Foster K2S/S-101, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S/S-101 is a 303 stainless steel 1/4" plu...

    View full details
    $ 28.59
    $ 28.59 - $ 28.59
    $ 28.59
    $ 22.89
    $ 22.89 - $ 22.89
    $ 22.89
    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 %
    $ 28.39
    $ 28.39 - $ 28.39
    $ 28.39
    $ 22.79
    $ 22.79 - $ 22.79
    $ 22.79

    Foster K2S/S-103, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2S/S-103 is a 303 stainless steel 1/4" plu...

    View full details
    $ 28.39
    $ 28.39 - $ 28.39
    $ 28.39
    $ 22.79
    $ 22.79 - $ 22.79
    $ 22.79
    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 %
    $ 28.89
    $ 28.89 - $ 28.89
    $ 28.89
    $ 23.19
    $ 23.19 - $ 23.19
    $ 23.19

    Foster K2S/S-104, 1/4" ISO-B Hydraulic Plug x 1/4" Female NPT, ISO-B Series, Silicone Seal, 303 Stainless Steel

    In stock

    Reliable, leak-free hydraulic connections built to the most widely used industrial standard. The Foster K2S/S-104 is a 303 stainless steel 1/4" plu...

    View full details
    $ 28.89
    $ 28.89 - $ 28.89
    $ 28.89
    $ 23.19
    $ 23.19 - $ 23.19
    $ 23.19
    Save 20% Save %