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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.

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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 243.00
$ 243.00 - $ 243.00
$ 243.00

Foster K3S, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S is a steel 3/8" plug in the FHK Serie...

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$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 243.00
$ 243.00 - $ 243.00
$ 243.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
$ 306.00 - $ 306.00
$ 306.00

Foster K3S-101, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Viton Seal, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S-101 is a steel 3/8" plug in the FHK S...

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$ 383.00
$ 383.00 - $ 383.00
$ 383.00
$ 306.00
$ 306.00 - $ 306.00
$ 306.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 370.00
$ 370.00 - $ 370.00
$ 370.00
$ 295.00
$ 295.00 - $ 295.00
$ 295.00

Foster K3S-102, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Neoprene Seal, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S-102 is a steel 3/8" plug in the FHK S...

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$ 370.00
$ 370.00 - $ 370.00
$ 370.00
$ 295.00
$ 295.00 - $ 295.00
$ 295.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 361.00
$ 361.00 - $ 361.00
$ 361.00
$ 288.00
$ 288.00 - $ 288.00
$ 288.00

Foster K3S-103, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, EPDM Seal, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S-103 is a steel 3/8" plug in the FHK S...

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$ 361.00
$ 361.00 - $ 361.00
$ 361.00
$ 288.00
$ 288.00 - $ 288.00
$ 288.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 299.00
$ 299.00 - $ 299.00
$ 299.00

Foster K3S-104, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Silicone Seal, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S-104 is a steel 3/8" plug in the FHK S...

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$ 374.00
$ 374.00 - $ 374.00
$ 374.00
$ 299.00
$ 299.00 - $ 299.00
$ 299.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 740.00
$ 740.00 - $ 740.00
$ 740.00
$ 592.00
$ 592.00 - $ 592.00
$ 592.00

Foster K3S/S, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, 303 Stainless Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S/S is a 303 stainless 3/8" plug in the...

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$ 740.00
$ 740.00 - $ 740.00
$ 740.00
$ 592.00
$ 592.00 - $ 592.00
$ 592.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 822.00
$ 822.00 - $ 822.00
$ 822.00
$ 656.00
$ 656.00 - $ 656.00
$ 656.00

Foster K3S/S-101, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Viton Seal, 303 Stainless Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S/S-101 is a 303 stainless 3/8" plug in...

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$ 822.00
$ 822.00 - $ 822.00
$ 822.00
$ 656.00
$ 656.00 - $ 656.00
$ 656.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 818.00
$ 818.00 - $ 818.00
$ 818.00
$ 654.00
$ 654.00 - $ 654.00
$ 654.00

Foster K3S/S-103, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, EPDM Seal, 303 Stainless Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S/S-103 is a 303 stainless 3/8" plug in...

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$ 818.00
$ 818.00 - $ 818.00
$ 818.00
$ 654.00
$ 654.00 - $ 654.00
$ 654.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 448.00
$ 448.00 - $ 448.00
$ 448.00
$ 359.00
$ 359.00 - $ 359.00
$ 359.00

Foster K3S8, 3/8" ISO-B Hydraulic Plug x 3/4"-16 SAE, ISO-B Series, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3S8 is a steel 3/8" plug in the FHK Seri...

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$ 448.00
$ 448.00 - $ 448.00
$ 448.00
$ 359.00
$ 359.00 - $ 359.00
$ 359.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 243.00
$ 243.00 - $ 243.00
$ 243.00

Foster K3SLV, 3/8" ISO-B Hydraulic Plug x 3/8" Female NPT, ISO-B Series, Less Valve, Plated Steel

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K3SLV is a steel 3/8" plug in the FHK Ser...

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$ 303.00
$ 303.00 - $ 303.00
$ 303.00
$ 243.00
$ 243.00 - $ 243.00
$ 243.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 487.00
$ 487.00 - $ 487.00
$ 487.00
$ 390.00
$ 390.00 - $ 390.00
$ 390.00

Foster K4B, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Brass

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4B is a brass 1/2" plug in the FHK Serie...

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$ 487.00
$ 487.00 - $ 487.00
$ 487.00
$ 390.00
$ 390.00 - $ 390.00
$ 390.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 625.00
$ 625.00 - $ 625.00
$ 625.00
$ 501.00
$ 501.00 - $ 501.00
$ 501.00

Foster K4B-101, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Viton Seal, Brass

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4B-101 is a brass 1/2" plug in the FHK S...

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$ 625.00
$ 625.00 - $ 625.00
$ 625.00
$ 501.00
$ 501.00 - $ 501.00
$ 501.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 609.00
$ 609.00 - $ 609.00
$ 609.00
$ 488.00
$ 488.00 - $ 488.00
$ 488.00

Foster K4B-102, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Neoprene Seal, Brass

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4B-102 is a brass 1/2" plug in the FHK S...

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$ 609.00
$ 609.00 - $ 609.00
$ 609.00
$ 488.00
$ 488.00 - $ 488.00
$ 488.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 587.00
$ 587.00 - $ 587.00
$ 587.00
$ 470.00
$ 470.00 - $ 470.00
$ 470.00

Foster K4B-103, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, EPDM Seal, Brass

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4B-103 is a brass 1/2" plug in the FHK S...

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$ 587.00
$ 587.00 - $ 587.00
$ 587.00
$ 470.00
$ 470.00 - $ 470.00
$ 470.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00

Foster K4BLV, 1/2" ISO-B Hydraulic Plug x 1/2" Female NPT, ISO-B Series, Less Valve, Brass

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4BLV is a brass 1/2" plug in the FHK Ser...

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$ 505.00
$ 505.00 - $ 505.00
$ 505.00
$ 405.00
$ 405.00 - $ 405.00
$ 405.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 314.00
$ 314.00 - $ 314.00
$ 314.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S is a steel 1/2" plug in the FHK Serie...

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$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 314.00
$ 314.00 - $ 314.00
$ 314.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 488.00
$ 488.00 - $ 488.00
$ 488.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S-101 is a steel 1/2" plug in the FHK S...

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$ 488.00
$ 488.00 - $ 488.00
$ 488.00
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 470.00
$ 470.00 - $ 470.00
$ 470.00
$ 376.00
$ 376.00 - $ 376.00
$ 376.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S-103 is a steel 1/2" plug in the FHK S...

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$ 470.00
$ 470.00 - $ 470.00
$ 470.00
$ 376.00
$ 376.00 - $ 376.00
$ 376.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 1,295.00
$ 1,295.00 - $ 1,295.00
$ 1,295.00
$ 1,037.00
$ 1,037.00 - $ 1,037.00
$ 1,037.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S/S is a 303 stainless 1/2" plug in the...

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$ 1,295.00
$ 1,295.00 - $ 1,295.00
$ 1,295.00
$ 1,037.00
$ 1,037.00 - $ 1,037.00
$ 1,037.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 1,401.00
$ 1,401.00 - $ 1,401.00
$ 1,401.00
$ 1,121.00
$ 1,121.00 - $ 1,121.00
$ 1,121.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S/S-101 is a 303 stainless 1/2" plug in...

View full details
$ 1,401.00
$ 1,401.00 - $ 1,401.00
$ 1,401.00
$ 1,121.00
$ 1,121.00 - $ 1,121.00
$ 1,121.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 1,419.00
$ 1,419.00 - $ 1,419.00
$ 1,419.00
$ 1,135.00
$ 1,135.00 - $ 1,135.00
$ 1,135.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S/S-103 is a 303 stainless 1/2" plug in...

View full details
$ 1,419.00
$ 1,419.00 - $ 1,419.00
$ 1,419.00
$ 1,135.00
$ 1,135.00 - $ 1,135.00
$ 1,135.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 1,321.00
$ 1,321.00 - $ 1,321.00
$ 1,321.00
$ 1,057.00
$ 1,057.00 - $ 1,057.00
$ 1,057.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S/SLV is a 303 stainless 1/2" plug in t...

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$ 1,321.00
$ 1,321.00 - $ 1,321.00
$ 1,321.00
$ 1,057.00
$ 1,057.00 - $ 1,057.00
$ 1,057.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 565.00
$ 565.00 - $ 565.00
$ 565.00
$ 452.00
$ 452.00 - $ 452.00
$ 452.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4S10 is a steel 1/2" plug in the FHK Ser...

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$ 565.00
$ 565.00 - $ 565.00
$ 565.00
$ 452.00
$ 452.00 - $ 452.00
$ 452.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 314.00
$ 314.00 - $ 314.00
$ 314.00

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

The most widely used industrial hydraulic quick coupling, compatible with ISO 7241-1 Series B. The Foster K4SLV is a steel 1/2" plug in the FHK Ser...

View full details
$ 392.00
$ 392.00 - $ 392.00
$ 392.00
$ 314.00
$ 314.00 - $ 314.00
$ 314.00
Save 20% Save %

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