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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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    $ 1,958.00
    $ 1,958.00 - $ 1,958.00
    $ 1,958.00
    $ 1,566.00
    $ 1,566.00 - $ 1,566.00
    $ 1,566.00

    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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    $ 1,958.00
    $ 1,958.00 - $ 1,958.00
    $ 1,958.00
    $ 1,566.00
    $ 1,566.00 - $ 1,566.00
    $ 1,566.00
    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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    $ 171.00
    $ 171.00 - $ 171.00
    $ 171.00
    $ 137.00
    $ 137.00 - $ 137.00
    $ 137.00

    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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    $ 171.00
    $ 171.00 - $ 171.00
    $ 171.00
    $ 137.00
    $ 137.00 - $ 137.00
    $ 137.00
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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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    $ 250.00
    $ 250.00 - $ 250.00
    $ 250.00
    $ 201.00
    $ 201.00 - $ 201.00
    $ 201.00

    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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    $ 250.00
    $ 250.00 - $ 250.00
    $ 250.00
    $ 201.00
    $ 201.00 - $ 201.00
    $ 201.00
    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 %
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00
    $ 190.00
    $ 190.00 - $ 190.00
    $ 190.00

    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
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00
    $ 190.00
    $ 190.00 - $ 190.00
    $ 190.00
    Save 19% 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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    $ 188.00
    $ 188.00 - $ 188.00
    $ 188.00
    $ 151.00
    $ 151.00 - $ 151.00
    $ 151.00

    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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    $ 188.00
    $ 188.00 - $ 188.00
    $ 188.00
    $ 151.00
    $ 151.00 - $ 151.00
    $ 151.00
    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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    $ 151.00
    $ 151.00 - $ 151.00
    $ 151.00
    $ 121.00
    $ 121.00 - $ 121.00
    $ 121.00

    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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    $ 151.00
    $ 151.00 - $ 151.00
    $ 151.00
    $ 121.00
    $ 121.00 - $ 121.00
    $ 121.00
    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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    $ 213.00
    $ 213.00 - $ 213.00
    $ 213.00
    $ 171.00
    $ 171.00 - $ 171.00
    $ 171.00

    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...

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    $ 213.00
    $ 213.00 - $ 213.00
    $ 213.00
    $ 171.00
    $ 171.00 - $ 171.00
    $ 171.00
    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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    $ 454.00
    $ 454.00 - $ 454.00
    $ 454.00
    $ 364.00
    $ 364.00 - $ 364.00
    $ 364.00

    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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    $ 454.00
    $ 454.00 - $ 454.00
    $ 454.00
    $ 364.00
    $ 364.00 - $ 364.00
    $ 364.00
    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 %
    $ 507.00
    $ 507.00 - $ 507.00
    $ 507.00
    $ 406.00
    $ 406.00 - $ 406.00
    $ 406.00

    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
    $ 507.00
    $ 507.00 - $ 507.00
    $ 507.00
    $ 406.00
    $ 406.00 - $ 406.00
    $ 406.00
    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 %
    $ 178.00
    $ 178.00 - $ 178.00
    $ 178.00
    $ 142.00
    $ 142.00 - $ 142.00
    $ 142.00

    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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    $ 178.00
    $ 178.00 - $ 178.00
    $ 178.00
    $ 142.00
    $ 142.00 - $ 142.00
    $ 142.00
    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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    $ 233.00
    $ 233.00 - $ 233.00
    $ 233.00
    $ 187.00
    $ 187.00 - $ 187.00
    $ 187.00

    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
    $ 233.00
    $ 233.00 - $ 233.00
    $ 233.00
    $ 187.00
    $ 187.00 - $ 187.00
    $ 187.00
    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 %
    $ 314.00
    $ 314.00 - $ 314.00
    $ 314.00
    $ 252.00
    $ 252.00 - $ 252.00
    $ 252.00

    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
    $ 314.00
    $ 314.00 - $ 314.00
    $ 314.00
    $ 252.00
    $ 252.00 - $ 252.00
    $ 252.00
    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 %
    $ 314.00
    $ 314.00 - $ 314.00
    $ 314.00
    $ 250.00
    $ 250.00 - $ 250.00
    $ 250.00

    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
    $ 314.00
    $ 314.00 - $ 314.00
    $ 314.00
    $ 250.00
    $ 250.00 - $ 250.00
    $ 250.00
    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 %
    $ 300.00
    $ 300.00 - $ 300.00
    $ 300.00
    $ 240.00
    $ 240.00 - $ 240.00
    $ 240.00

    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
    $ 300.00
    $ 300.00 - $ 300.00
    $ 300.00
    $ 240.00
    $ 240.00 - $ 240.00
    $ 240.00
    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 %
    $ 325.00
    $ 325.00 - $ 325.00
    $ 325.00
    $ 261.00
    $ 261.00 - $ 261.00
    $ 261.00

    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
    $ 325.00
    $ 325.00 - $ 325.00
    $ 325.00
    $ 261.00
    $ 261.00 - $ 261.00
    $ 261.00
    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 %
    $ 245.00
    $ 245.00 - $ 245.00
    $ 245.00
    $ 197.00
    $ 197.00 - $ 197.00
    $ 197.00

    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
    $ 245.00
    $ 245.00 - $ 245.00
    $ 245.00
    $ 197.00
    $ 197.00 - $ 197.00
    $ 197.00
    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 %
    $ 201.00
    $ 201.00 - $ 201.00
    $ 201.00
    $ 162.00
    $ 162.00 - $ 162.00
    $ 162.00

    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
    $ 201.00
    $ 201.00 - $ 201.00
    $ 201.00
    $ 162.00
    $ 162.00 - $ 162.00
    $ 162.00
    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 %
    $ 261.00
    $ 261.00 - $ 261.00
    $ 261.00
    $ 210.00
    $ 210.00 - $ 210.00
    $ 210.00

    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
    $ 261.00
    $ 261.00 - $ 261.00
    $ 261.00
    $ 210.00
    $ 210.00 - $ 210.00
    $ 210.00
    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 %
    $ 257.00
    $ 257.00 - $ 257.00
    $ 257.00
    $ 206.00
    $ 206.00 - $ 206.00
    $ 206.00

    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
    $ 257.00
    $ 257.00 - $ 257.00
    $ 257.00
    $ 206.00
    $ 206.00 - $ 206.00
    $ 206.00
    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 %
    $ 265.00
    $ 265.00 - $ 265.00
    $ 265.00
    $ 211.00
    $ 211.00 - $ 211.00
    $ 211.00

    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
    $ 265.00
    $ 265.00 - $ 265.00
    $ 265.00
    $ 211.00
    $ 211.00 - $ 211.00
    $ 211.00
    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 %
    $ 444.00
    $ 444.00 - $ 444.00
    $ 444.00
    $ 355.00
    $ 355.00 - $ 355.00
    $ 355.00

    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
    $ 444.00
    $ 444.00 - $ 444.00
    $ 444.00
    $ 355.00
    $ 355.00 - $ 355.00
    $ 355.00
    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 %
    $ 507.00
    $ 507.00 - $ 507.00
    $ 507.00
    $ 406.00
    $ 406.00 - $ 406.00
    $ 406.00

    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
    $ 507.00
    $ 507.00 - $ 507.00
    $ 507.00
    $ 406.00
    $ 406.00 - $ 406.00
    $ 406.00
    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 %
    $ 504.00
    $ 504.00 - $ 504.00
    $ 504.00
    $ 405.00
    $ 405.00 - $ 405.00
    $ 405.00

    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
    $ 504.00
    $ 504.00 - $ 504.00
    $ 504.00
    $ 405.00
    $ 405.00 - $ 405.00
    $ 405.00
    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 %
    $ 513.00
    $ 513.00 - $ 513.00
    $ 513.00
    $ 412.00
    $ 412.00 - $ 412.00
    $ 412.00

    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
    $ 513.00
    $ 513.00 - $ 513.00
    $ 513.00
    $ 412.00
    $ 412.00 - $ 412.00
    $ 412.00
    Save 20% Save %