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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 %
$ 16.59
$ 16.59 - $ 16.59
$ 16.59
$ 13.29
$ 13.29 - $ 13.29
$ 13.29

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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$ 16.59
$ 16.59 - $ 16.59
$ 16.59
$ 13.29
$ 13.29 - $ 13.29
$ 13.29
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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 %
$ 20.99
$ 20.99 - $ 20.99
$ 20.99
$ 16.79
$ 16.79 - $ 16.79
$ 16.79

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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$ 20.99
$ 20.99 - $ 20.99
$ 20.99
$ 16.79
$ 16.79 - $ 16.79
$ 16.79
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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 %
$ 20.29
$ 20.29 - $ 20.29
$ 20.29
$ 16.19
$ 16.19 - $ 16.19
$ 16.19

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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$ 20.29
$ 20.29 - $ 20.29
$ 20.29
$ 16.19
$ 16.19 - $ 16.19
$ 16.19
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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 %
$ 19.79
$ 19.79 - $ 19.79
$ 19.79
$ 15.79
$ 15.79 - $ 15.79
$ 15.79

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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$ 19.79
$ 19.79 - $ 19.79
$ 19.79
$ 15.79
$ 15.79 - $ 15.79
$ 15.79
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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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$ 20.49
$ 20.49 - $ 20.49
$ 20.49
$ 16.39
$ 16.39 - $ 16.39
$ 16.39

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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$ 20.49
$ 20.49 - $ 20.49
$ 20.49
$ 16.39
$ 16.39 - $ 16.39
$ 16.39
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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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$ 40.59
$ 40.59 - $ 40.59
$ 40.59
$ 32.49
$ 32.49 - $ 32.49
$ 32.49

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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$ 40.59
$ 40.59 - $ 40.59
$ 40.59
$ 32.49
$ 32.49 - $ 32.49
$ 32.49
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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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$ 45.09
$ 45.09 - $ 45.09
$ 45.09
$ 35.99
$ 35.99 - $ 35.99
$ 35.99

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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$ 45.09
$ 45.09 - $ 45.09
$ 45.09
$ 35.99
$ 35.99 - $ 35.99
$ 35.99
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 %
$ 44.89
$ 44.89 - $ 44.89
$ 44.89
$ 35.89
$ 35.89 - $ 35.89
$ 35.89

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...

View full details
$ 44.89
$ 44.89 - $ 44.89
$ 44.89
$ 35.89
$ 35.89 - $ 35.89
$ 35.89
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 %
$ 24.59
$ 24.59 - $ 24.59
$ 24.59
$ 19.69
$ 19.69 - $ 19.69
$ 19.69

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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$ 24.59
$ 24.59 - $ 24.59
$ 24.59
$ 19.69
$ 19.69 - $ 19.69
$ 19.69
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 %
$ 16.59
$ 16.59 - $ 16.59
$ 16.59
$ 13.29
$ 13.29 - $ 13.29
$ 13.29

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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$ 16.59
$ 16.59 - $ 16.59
$ 16.59
$ 13.29
$ 13.29 - $ 13.29
$ 13.29
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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$ 26.69
$ 26.69 - $ 26.69
$ 26.69
$ 21.39
$ 21.39 - $ 21.39
$ 21.39

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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$ 26.69
$ 26.69 - $ 26.69
$ 26.69
$ 21.39
$ 21.39 - $ 21.39
$ 21.39
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 %
$ 34.29
$ 34.29 - $ 34.29
$ 34.29
$ 27.49
$ 27.49 - $ 27.49
$ 27.49

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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$ 34.29
$ 34.29 - $ 34.29
$ 34.29
$ 27.49
$ 27.49 - $ 27.49
$ 27.49
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 %
$ 33.39
$ 33.39 - $ 33.39
$ 33.39
$ 26.79
$ 26.79 - $ 26.79
$ 26.79

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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$ 33.39
$ 33.39 - $ 33.39
$ 33.39
$ 26.79
$ 26.79 - $ 26.79
$ 26.79
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 %
$ 32.19
$ 32.19 - $ 32.19
$ 32.19
$ 25.79
$ 25.79 - $ 25.79
$ 25.79

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...

View full details
$ 32.19
$ 32.19 - $ 32.19
$ 32.19
$ 25.79
$ 25.79 - $ 25.79
$ 25.79
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 %
$ 27.69
$ 27.69 - $ 27.69
$ 27.69
$ 22.19
$ 22.19 - $ 22.19
$ 22.19

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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$ 27.69
$ 27.69 - $ 27.69
$ 27.69
$ 22.19
$ 22.19 - $ 22.19
$ 22.19
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 %
$ 21.49
$ 21.49 - $ 21.49
$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19

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...

View full details
$ 21.49
$ 21.49 - $ 21.49
$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19
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 %
$ 26.79
$ 26.79 - $ 26.79
$ 26.79
$ 21.49
$ 21.49 - $ 21.49
$ 21.49

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...

View full details
$ 26.79
$ 26.79 - $ 26.79
$ 26.79
$ 21.49
$ 21.49 - $ 21.49
$ 21.49
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 %
$ 25.79
$ 25.79 - $ 25.79
$ 25.79
$ 20.59
$ 20.59 - $ 20.59
$ 20.59

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...

View full details
$ 25.79
$ 25.79 - $ 25.79
$ 25.79
$ 20.59
$ 20.59 - $ 20.59
$ 20.59
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 %
$ 71.09
$ 71.09 - $ 71.09
$ 71.09
$ 56.89
$ 56.89 - $ 56.89
$ 56.89

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...

View full details
$ 71.09
$ 71.09 - $ 71.09
$ 71.09
$ 56.89
$ 56.89 - $ 56.89
$ 56.89
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 %
$ 76.89
$ 76.89 - $ 76.89
$ 76.89
$ 61.49
$ 61.49 - $ 61.49
$ 61.49

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
$ 76.89
$ 76.89 - $ 76.89
$ 76.89
$ 61.49
$ 61.49 - $ 61.49
$ 61.49
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 %
$ 77.89
$ 77.89 - $ 77.89
$ 77.89
$ 62.29
$ 62.29 - $ 62.29
$ 62.29

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
$ 77.89
$ 77.89 - $ 77.89
$ 77.89
$ 62.29
$ 62.29 - $ 62.29
$ 62.29
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 %
$ 72.49
$ 72.49 - $ 72.49
$ 72.49
$ 57.99
$ 57.99 - $ 57.99
$ 57.99

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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$ 72.49
$ 72.49 - $ 72.49
$ 72.49
$ 57.99
$ 57.99 - $ 57.99
$ 57.99
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 %
$ 30.99
$ 30.99 - $ 30.99
$ 30.99
$ 24.79
$ 24.79 - $ 24.79
$ 24.79

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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$ 30.99
$ 30.99 - $ 30.99
$ 30.99
$ 24.79
$ 24.79 - $ 24.79
$ 24.79
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 %
$ 21.49
$ 21.49 - $ 21.49
$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19

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
$ 21.49
$ 21.49 - $ 21.49
$ 21.49
$ 17.19
$ 17.19 - $ 17.19
$ 17.19
Save 20% Save %

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