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Foster

Foster quick couplers set the standard in pneumatic and hydraulic connections. Part of the ZSI-Foster line, Foster couplers and plugs cover the full range of industrial interchanges and body sizes in steel, brass, and stainless construction. Built for reliable, repeatable connections in air and fluid systems. Shop the full Foster range below.

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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 %
$ 26.89
$ 26.89 - $ 26.89
$ 26.89
$ 21.49
$ 21.49 - $ 21.49
$ 21.49

Foster 71-4B, 3/8" Industrial Plug x 3/8" Push-On Hose Stem, 4 Series, Brass

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 71-4B is a Brass 3/8" industrial plug from the Foster 4 Series — a high-fl...

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$ 26.89
$ 26.89 - $ 26.89
$ 26.89
$ 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 %
$ 6.39
$ 6.39 - $ 6.39
$ 6.39
$ 5.09
$ 5.09 - $ 5.09
$ 5.09

Foster 71-4, 3/8" Industrial Plug x 3/8" Push-On Hose Stem, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 71-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 6.39
$ 6.39 - $ 6.39
$ 6.39
$ 5.09
$ 5.09 - $ 5.09
$ 5.09
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 19% Save %
$ 7.39
$ 7.39 - $ 7.39
$ 7.39
$ 5.99
$ 5.99 - $ 5.99
$ 5.99

Foster 51-4, 3/8" Industrial Plug x 1/4" Push-On Hose Stem, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 51-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 7.39
$ 7.39 - $ 7.39
$ 7.39
$ 5.99
$ 5.99 - $ 5.99
$ 5.99
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 6.99
$ 6.99 - $ 6.99
$ 6.99
$ 5.59
$ 5.59 - $ 5.59
$ 5.59

Foster 49-4, 3/8" Industrial Plug x 1/2" Hose ID, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 49-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 6.99
$ 6.99 - $ 6.99
$ 6.99
$ 5.59
$ 5.59 - $ 5.59
$ 5.59
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 19% Save %
$ 9.89
$ 9.89 - $ 9.89
$ 9.89
$ 7.99
$ 7.99 - $ 7.99
$ 7.99

Foster 48-4B, 3/8" Industrial Plug x 3/8" Hose ID, 4 Series, Brass

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 48-4B is a Brass 3/8" industrial plug from the Foster 4 Series — a high-fl...

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$ 9.89
$ 9.89 - $ 9.89
$ 9.89
$ 7.99
$ 7.99 - $ 7.99
$ 7.99
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 6.29
$ 6.29 - $ 6.29
$ 6.29
$ 4.99
$ 4.99 - $ 4.99
$ 4.99

Foster 48-4, 3/8" Industrial Plug x 3/8" Hose ID, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 48-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 6.29
$ 6.29 - $ 6.29
$ 6.29
$ 4.99
$ 4.99 - $ 4.99
$ 4.99
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 10.39
$ 10.39 - $ 10.39
$ 10.39
$ 8.29
$ 8.29 - $ 8.29
$ 8.29

Foster 47-4, 3/8" Industrial Plug x 5/16" Hose ID, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 47-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 10.39
$ 10.39 - $ 10.39
$ 10.39
$ 8.29
$ 8.29 - $ 8.29
$ 8.29
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 %
$ 8.79
$ 8.79 - $ 8.79
$ 8.79
$ 6.99
$ 6.99 - $ 6.99
$ 6.99

Foster 46-4, 3/8" Industrial Plug x 1/4" Hose ID, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 46-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 8.79
$ 8.79 - $ 8.79
$ 8.79
$ 6.99
$ 6.99 - $ 6.99
$ 6.99
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 %
$ 17.19
$ 17.19 - $ 17.19
$ 17.19
$ 13.69
$ 13.69 - $ 13.69
$ 13.69

Foster 44S-4, 3/8" Industrial Plug x 1/2" Male NPT, 4 Series, Free Swivel, Brass/Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 44S-4 is a Brass/Steel 3/8" industrial plug from the Foster 4 Series — a h...

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$ 17.19
$ 17.19 - $ 17.19
$ 17.19
$ 13.69
$ 13.69 - $ 13.69
$ 13.69
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 %
$ 12.99
$ 12.99 - $ 12.99
$ 12.99
$ 10.39
$ 10.39 - $ 10.39
$ 10.39

Foster 42S-4, 3/8" Industrial Plug x 3/8" Male NPT, 4 Series, Free Swivel, Brass/Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 42S-4 is a Brass/Steel 3/8" industrial plug from the Foster 4 Series — a h...

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$ 12.99
$ 12.99 - $ 12.99
$ 12.99
$ 10.39
$ 10.39 - $ 10.39
$ 10.39
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 %
$ 20.09
$ 20.09 - $ 20.09
$ 20.09
$ 16.09
$ 16.09 - $ 16.09
$ 16.09

Foster 40S-4, 3/8" Industrial Plug x 1/4" Male NPT, 4 Series, Free Swivel, Brass/Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 40S-4 is a Brass/Steel 3/8" industrial plug from the Foster 4 Series — a h...

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$ 20.09
$ 20.09 - $ 20.09
$ 20.09
$ 16.09
$ 16.09 - $ 16.09
$ 16.09
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 %
$ 6.99
$ 6.99 - $ 6.99
$ 6.99
$ 5.59
$ 5.59 - $ 5.59
$ 5.59

Foster 44-4, 3/8" Industrial Plug x 1/2" Male NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 44-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

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$ 6.99
$ 6.99 - $ 6.99
$ 6.99
$ 5.59
$ 5.59 - $ 5.59
$ 5.59
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 %
$ 14.49
$ 14.49 - $ 14.49
$ 14.49
$ 11.59
$ 11.59 - $ 11.59
$ 11.59

Foster 42-4S/S, 3/8" Industrial Plug x 3/8" Male NPT, 4 Series, 303 Stainless

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 42-4S/S is a 303 Stainless 3/8" industrial plug from the Foster 4 Series —...

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$ 14.49
$ 14.49 - $ 14.49
$ 14.49
$ 11.59
$ 11.59 - $ 11.59
$ 11.59
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 %
$ 8.99
$ 8.99 - $ 8.99
$ 8.99
$ 7.19
$ 7.19 - $ 7.19
$ 7.19

Foster 42-4B, 3/8" Industrial Plug x 3/8" Male NPT, 4 Series, Brass

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 42-4B is a Brass 3/8" industrial plug from the Foster 4 Series — a high-fl...

View full details
$ 8.99
$ 8.99 - $ 8.99
$ 8.99
$ 7.19
$ 7.19 - $ 7.19
$ 7.19
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 %
$ 4.99
$ 4.99 - $ 4.99
$ 4.99
$ 3.99
$ 3.99 - $ 3.99
$ 3.99

Foster 42-4, 3/8" Industrial Plug x 3/8" Male NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 42-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 4.99
$ 4.99 - $ 4.99
$ 4.99
$ 3.99
$ 3.99 - $ 3.99
$ 3.99
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 %
$ 10.49
$ 10.49 - $ 10.49
$ 10.49
$ 8.39
$ 8.39 - $ 8.39
$ 8.39

Foster 40-4S/S, 3/8" Industrial Plug x 1/4" Male NPT, 4 Series, 303 Stainless

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 40-4S/S is a 303 Stainless 3/8" industrial plug from the Foster 4 Series —...

View full details
$ 10.49
$ 10.49 - $ 10.49
$ 10.49
$ 8.39
$ 8.39 - $ 8.39
$ 8.39
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 9.19
$ 9.19 - $ 9.19
$ 9.19
$ 7.29
$ 7.29 - $ 7.29
$ 7.29

Foster 40-4B, 3/8" Industrial Plug x 1/4" Male NPT, 4 Series, Brass

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 40-4B is a Brass 3/8" industrial plug from the Foster 4 Series — a high-fl...

View full details
$ 9.19
$ 9.19 - $ 9.19
$ 9.19
$ 7.29
$ 7.29 - $ 7.29
$ 7.29
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 5.39
$ 5.39 - $ 5.39
$ 5.39
$ 4.29
$ 4.29 - $ 4.29
$ 4.29

Foster 40-4, 3/8" Industrial Plug x 1/4" Male NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 40-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 5.39
$ 5.39 - $ 5.39
$ 5.39
$ 4.29
$ 4.29 - $ 4.29
$ 4.29
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 %
$ 11.39
$ 11.39 - $ 11.39
$ 11.39
$ 9.09
$ 9.09 - $ 9.09
$ 9.09

Foster 38-4, 3/8" Industrial Plug x 1/8" Male NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 38-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 11.39
$ 11.39 - $ 11.39
$ 11.39
$ 9.09
$ 9.09 - $ 9.09
$ 9.09
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 %
$ 9.29
$ 9.29 - $ 9.29
$ 9.29
$ 7.39
$ 7.39 - $ 7.39
$ 7.39

Foster 45-4, 3/8" Industrial Plug x 1/2" Female NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 45-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 9.29
$ 9.29 - $ 9.29
$ 9.29
$ 7.39
$ 7.39 - $ 7.39
$ 7.39
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 %
$ 19.39
$ 19.39 - $ 19.39
$ 19.39
$ 15.49
$ 15.49 - $ 15.49
$ 15.49

Foster 43-4S/S, 3/8" Industrial Plug x 3/8" Female NPT, 4 Series, 303 Stainless

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 43-4S/S is a 303 Stainless 3/8" industrial plug from the Foster 4 Series —...

View full details
$ 19.39
$ 19.39 - $ 19.39
$ 19.39
$ 15.49
$ 15.49 - $ 15.49
$ 15.49
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 19% Save %
$ 6.69
$ 6.69 - $ 6.69
$ 6.69
$ 5.39
$ 5.39 - $ 5.39
$ 5.39

Foster 43-4, 3/8" Industrial Plug x 3/8" Female NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 43-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 6.69
$ 6.69 - $ 6.69
$ 6.69
$ 5.39
$ 5.39 - $ 5.39
$ 5.39
Save 19% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 5.39
$ 5.39 - $ 5.39
$ 5.39
$ 4.29
$ 4.29 - $ 4.29
$ 4.29

Foster 41-4, 3/8" Industrial Plug x 1/4" Female NPT, 4 Series, Steel

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster 41-4 is a Steel 3/8" industrial plug from the Foster 4 Series — a high-flo...

View full details
$ 5.39
$ 5.39 - $ 5.39
$ 5.39
$ 4.29
$ 4.29 - $ 4.29
$ 4.29
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 %
$ 44.19
$ 44.19 - $ 44.19
$ 44.19
$ 35.39
$ 35.39 - $ 35.39
$ 35.39

Foster SLSD13-4, 3/8" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 13/16" OD, 4 Series, Automatic Sleeve Lock, Brass

Reliable, leak-free 3/8" connections for air and fluid lines. The Foster SLSD13-4 is a Brass 3/8" industrial coupler from the Foster 4 Series — a h...

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$ 44.19
$ 44.19 - $ 44.19
$ 44.19
$ 35.39
$ 35.39 - $ 35.39
$ 35.39
Save 20% Save %

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