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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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    $ 452.00
    $ 452.00 - $ 452.00
    $ 452.00
    $ 362.00
    $ 362.00 - $ 362.00
    $ 362.00

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

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    $ 452.00
    $ 452.00 - $ 452.00
    $ 452.00
    $ 362.00
    $ 362.00 - $ 362.00
    $ 362.00
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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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    $ 289.00
    $ 289.00 - $ 289.00
    $ 289.00
    $ 231.00
    $ 231.00 - $ 231.00
    $ 231.00

    Foster K2S6, 1/4" ISO-B Hydraulic Plug 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 K2S6 is a plated steel 1/4" plug from the I...

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    $ 289.00
    $ 289.00 - $ 289.00
    $ 289.00
    $ 231.00
    $ 231.00 - $ 231.00
    $ 231.00
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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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    $ 204.00
    $ 204.00 - $ 204.00
    $ 204.00
    $ 163.00
    $ 163.00 - $ 163.00
    $ 163.00

    Foster K2SLV, 1/4" ISO-B Hydraulic Plug x 1/4" 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 K2SLV is a plated steel 1/4" plug from the ...

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    $ 204.00
    $ 204.00 - $ 204.00
    $ 204.00
    $ 163.00
    $ 163.00 - $ 163.00
    $ 163.00
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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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    $ 323.00
    $ 323.00 - $ 323.00
    $ 323.00
    $ 259.00
    $ 259.00 - $ 259.00
    $ 259.00

    Foster K3B, 3/8" ISO-B Hydraulic Plug 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 K3B is a brass 3/8" plug from the ISO-B Ser...

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    $ 323.00
    $ 323.00 - $ 323.00
    $ 323.00
    $ 259.00
    $ 259.00 - $ 259.00
    $ 259.00
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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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    $ 433.00
    $ 433.00 - $ 433.00
    $ 433.00
    $ 348.00
    $ 348.00 - $ 348.00
    $ 348.00

    Foster K3B-101, 3/8" ISO-B Hydraulic Plug 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 K3B-101 is a brass 3/8" plug from the ISO-B...

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    $ 433.00
    $ 433.00 - $ 433.00
    $ 433.00
    $ 348.00
    $ 348.00 - $ 348.00
    $ 348.00
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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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    $ 422.00
    $ 422.00 - $ 422.00
    $ 422.00
    $ 339.00
    $ 339.00 - $ 339.00
    $ 339.00

    Foster K3B-102, 3/8" ISO-B Hydraulic Plug 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 K3B-102 is a brass 3/8" plug from the ISO-B...

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    $ 422.00
    $ 422.00 - $ 422.00
    $ 422.00
    $ 339.00
    $ 339.00 - $ 339.00
    $ 339.00
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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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    $ 396.00
    $ 396.00 - $ 396.00
    $ 396.00
    $ 318.00
    $ 318.00 - $ 318.00
    $ 318.00

    Foster K3B-103, 3/8" ISO-B Hydraulic Plug 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 K3B-103 is a brass 3/8" plug from the ISO-B...

    View full details
    $ 396.00
    $ 396.00 - $ 396.00
    $ 396.00
    $ 318.00
    $ 318.00 - $ 318.00
    $ 318.00
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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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    $ 295.00
    $ 295.00 - $ 295.00
    $ 295.00
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00

    Foster K3S, 3/8" ISO-B Hydraulic Plug 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 K3S is a plated steel 3/8" plug from the IS...

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    $ 295.00
    $ 295.00 - $ 295.00
    $ 295.00
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00
    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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    $ 373.00
    $ 373.00 - $ 373.00
    $ 373.00
    $ 298.00
    $ 298.00 - $ 298.00
    $ 298.00

    Foster K3S-101, 3/8" ISO-B Hydraulic Plug 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 K3S-101 is a plated steel 3/8" plug from th...

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    $ 373.00
    $ 373.00 - $ 373.00
    $ 373.00
    $ 298.00
    $ 298.00 - $ 298.00
    $ 298.00
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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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    $ 360.00
    $ 360.00 - $ 360.00
    $ 360.00
    $ 288.00
    $ 288.00 - $ 288.00
    $ 288.00

    Foster K3S-102, 3/8" ISO-B Hydraulic Plug 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 K3S-102 is a plated steel 3/8" plug from th...

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    $ 360.00
    $ 360.00 - $ 360.00
    $ 360.00
    $ 288.00
    $ 288.00 - $ 288.00
    $ 288.00
    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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    $ 351.00
    $ 351.00 - $ 351.00
    $ 351.00
    $ 280.00
    $ 280.00 - $ 280.00
    $ 280.00

    Foster K3S-103, 3/8" ISO-B Hydraulic Plug 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 K3S-103 is a plated steel 3/8" plug from th...

    View full details
    $ 351.00
    $ 351.00 - $ 351.00
    $ 351.00
    $ 280.00
    $ 280.00 - $ 280.00
    $ 280.00
    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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    $ 364.00
    $ 364.00 - $ 364.00
    $ 364.00
    $ 291.00
    $ 291.00 - $ 291.00
    $ 291.00

    Foster K3S-104, 3/8" ISO-B Hydraulic Plug 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 K3S-104 is a plated steel 3/8" plug from th...

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    $ 364.00
    $ 364.00 - $ 364.00
    $ 364.00
    $ 291.00
    $ 291.00 - $ 291.00
    $ 291.00
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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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    $ 720.00
    $ 720.00 - $ 720.00
    $ 720.00
    $ 577.00
    $ 577.00 - $ 577.00
    $ 577.00

    Foster K3S/S, 3/8" ISO-B Hydraulic Plug 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 K3S/S is a 303 stainless steel 3/8" plug fr...

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    $ 720.00
    $ 720.00 - $ 720.00
    $ 720.00
    $ 577.00
    $ 577.00 - $ 577.00
    $ 577.00
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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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    $ 800.00
    $ 800.00 - $ 800.00
    $ 800.00
    $ 639.00
    $ 639.00 - $ 639.00
    $ 639.00

    Foster K3S/S-101, 3/8" ISO-B Hydraulic Plug 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 K3S/S-101 is a 303 stainless steel 3/8" plu...

    View full details
    $ 800.00
    $ 800.00 - $ 800.00
    $ 800.00
    $ 639.00
    $ 639.00 - $ 639.00
    $ 639.00
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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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    $ 797.00
    $ 797.00 - $ 797.00
    $ 797.00
    $ 637.00
    $ 637.00 - $ 637.00
    $ 637.00

    Foster K3S/S-103, 3/8" ISO-B Hydraulic Plug x 3/8" 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 K3S/S-103 is a 303 stainless steel 3/8" plu...

    View full details
    $ 797.00
    $ 797.00 - $ 797.00
    $ 797.00
    $ 637.00
    $ 637.00 - $ 637.00
    $ 637.00
    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 %
    $ 437.00
    $ 437.00 - $ 437.00
    $ 437.00
    $ 350.00
    $ 350.00 - $ 350.00
    $ 350.00

    Foster K3S8, 3/8" ISO-B Hydraulic Plug 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 K3S8 is a plated steel 3/8" plug from the I...

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    $ 437.00
    $ 437.00 - $ 437.00
    $ 437.00
    $ 350.00
    $ 350.00 - $ 350.00
    $ 350.00
    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 %
    $ 295.00
    $ 295.00 - $ 295.00
    $ 295.00
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00

    Foster K3SLV, 3/8" ISO-B Hydraulic Plug x 3/8" 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 K3SLV is a plated steel 3/8" plug from the ...

    View full details
    $ 295.00
    $ 295.00 - $ 295.00
    $ 295.00
    $ 236.00
    $ 236.00 - $ 236.00
    $ 236.00
    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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    $ 474.00
    $ 474.00 - $ 474.00
    $ 474.00
    $ 380.00
    $ 380.00 - $ 380.00
    $ 380.00

    Foster K4B, 1/2" ISO-B Hydraulic Plug 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 K4B is a brass 1/2" plug from the ISO-B Ser...

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    $ 474.00
    $ 474.00 - $ 474.00
    $ 474.00
    $ 380.00
    $ 380.00 - $ 380.00
    $ 380.00
    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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    $ 609.00
    $ 609.00 - $ 609.00
    $ 609.00
    $ 488.00
    $ 488.00 - $ 488.00
    $ 488.00

    Foster K4B-101, 1/2" ISO-B Hydraulic Plug 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 K4B-101 is a brass 1/2" plug from the ISO-B...

    View full details
    $ 609.00
    $ 609.00 - $ 609.00
    $ 609.00
    $ 488.00
    $ 488.00 - $ 488.00
    $ 488.00
    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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    $ 593.00
    $ 593.00 - $ 593.00
    $ 593.00
    $ 476.00
    $ 476.00 - $ 476.00
    $ 476.00

    Foster K4B-102, 1/2" ISO-B Hydraulic Plug 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 K4B-102 is a brass 1/2" plug from the ISO-B...

    View full details
    $ 593.00
    $ 593.00 - $ 593.00
    $ 593.00
    $ 476.00
    $ 476.00 - $ 476.00
    $ 476.00
    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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    $ 571.00
    $ 571.00 - $ 571.00
    $ 571.00
    $ 458.00
    $ 458.00 - $ 458.00
    $ 458.00

    Foster K4B-103, 1/2" ISO-B Hydraulic Plug 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 K4B-103 is a brass 1/2" plug from the ISO-B...

    View full details
    $ 571.00
    $ 571.00 - $ 571.00
    $ 571.00
    $ 458.00
    $ 458.00 - $ 458.00
    $ 458.00
    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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    $ 492.00
    $ 492.00 - $ 492.00
    $ 492.00
    $ 394.00
    $ 394.00 - $ 394.00
    $ 394.00

    Foster K4BLV, 1/2" ISO-B Hydraulic Plug x 1/2" 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 K4BLV is a brass 1/2" plug from the ISO-B S...

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    $ 492.00
    $ 492.00 - $ 492.00
    $ 492.00
    $ 394.00
    $ 394.00 - $ 394.00
    $ 394.00
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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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    $ 382.00
    $ 382.00 - $ 382.00
    $ 382.00
    $ 305.00
    $ 305.00 - $ 305.00
    $ 305.00

    Foster K4S, 1/2" ISO-B Hydraulic Plug 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 K4S is a plated steel 1/2" plug from the IS...

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    $ 382.00
    $ 382.00 - $ 382.00
    $ 382.00
    $ 305.00
    $ 305.00 - $ 305.00
    $ 305.00
    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 %
    $ 476.00
    $ 476.00 - $ 476.00
    $ 476.00
    $ 382.00
    $ 382.00 - $ 382.00
    $ 382.00

    Foster K4S-101, 1/2" ISO-B Hydraulic Plug 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 K4S-101 is a plated steel 1/2" plug from th...

    View full details
    $ 476.00
    $ 476.00 - $ 476.00
    $ 476.00
    $ 382.00
    $ 382.00 - $ 382.00
    $ 382.00
    Save 20% Save %