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ZSI Foster - 4 Series, 3/8" Body Industrial Interchange Pneumatic Couplers and Plugs

ZSI Foster's "4 Series" pneumatic fittings are the perfect solution for your industrial and manufacturing needs, including construction and repair shops. Made of durable brass or steel, these fittings are designed to connect flexible tubing such as polyurethane and nylon in various sizes. The quick-connect design allows for easy attachment and detachment from your pneumatic system, while their 3/8" industrial interchange compatibility means they can be used with fittings from other manufacturers. With their reliability and versatility, the "4 Series" fittings are a top choice for a wide range of pneumatic applications in construction and repair shops. Trust ZSI Foster to deliver high-quality fittings that get the job done right.
  • Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
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    Current price $ 4.59

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

    In stock

    Series: 4 Part Number: 40-4 Interchange: Industrial Body: 3/8" Plug Thread: 1/4" Male NPT, MPT Material: Heavy-Duty Steel Rated Pressure:...

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    Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59
  • Original price $ 19.49 - Original price $ 19.49
    Original price
    $ 19.49
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    Current price $ 19.49

    Foster FM4204, 4 Series, Industrial Coupler, Automatic, 3/8" Female NPT, Brass

    In stock

    Series: 4 Part Number: FM4204 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 3/8" Female NPT, FPT Material: Heavy-Duty Bras...

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    Original price $ 19.49 - Original price $ 19.49
    Original price
    $ 19.49
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    Current price $ 19.49
  • Original price $ 3.99 - Original price $ 3.99
    Original price
    $ 3.99
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    Current price $ 3.99

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

    In stock

    Series: 4 Part Number: 43-4 Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Female NPT, FPT Material: Heavy-Duty Brass Rated Pressur...

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    Original price $ 3.99 - Original price $ 3.99
    Original price
    $ 3.99
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    Current price $ 3.99
  • Original price $ 3.69 - Original price $ 3.69
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    $ 3.69
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    Current price $ 3.69

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

    In stock

    Series: 4 Part Number: 42-4 Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Male NPT, MPT Material: Heavy-Duty Steel Rated Pressure:...

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    Original price $ 3.69 - Original price $ 3.69
    Original price
    $ 3.69
    $ 3.69 - $ 3.69
    Current price $ 3.69
  • Original price $ 19.49 - Original price $ 19.49
    Original price
    $ 19.49
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    Current price $ 19.49

    Foster FM4303, 4 Series, Industrial Coupler, Automatic, 3/8" Male NPT, Brass

    In stock

    Series: 4 Part Number: FM4304 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 3/8" Male NPT, MPT Material: Heavy-Duty Brass,...

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    Original price $ 19.49 - Original price $ 19.49
    Original price
    $ 19.49
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    Current price $ 19.49
  • Original price $ 19.99 - Original price $ 19.99
    Original price
    $ 19.99
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    Current price $ 19.99

    Foster FM4404, 4 Series, Industrial Coupler, Automatic, 1/2" Female NPT, Brass

    In stock

    Series: 4 Part Number: FM4404 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 1/2" Female NPT, FPT Material: Heavy-Duty Bras...

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    Original price $ 19.99 - Original price $ 19.99
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    $ 19.99
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    Current price $ 19.99
  • Original price $ 14.79 - Original price $ 14.79
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    $ 14.79
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    Current price $ 14.79

    Foster 4104, 4 Series, Industrial Coupler, Manual, 1/4" Male NPT, Brass, Steel

    In stock

    Series: 4 Part Number: 4104 Interchange: Industrial, I/M Body: 3/8" Manual Coupler Thread: 1/4" Male NPT, MPT Material: Heavy-Duty Brass, ...

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    Original price $ 14.79 - Original price $ 14.79
    Original price
    $ 14.79
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    Current price $ 14.79
  • Original price $ 5.29 - Original price $ 5.29
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    Current price $ 5.29

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

    In stock

    Series: 4 Part Number: 45-4 Interchange: Industrial Body: 3/8" Plug Thread: 1/2" Female NPT, FPT Material: Heavy-Duty Steel Rated Pressur...

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    Original price $ 5.29 - Original price $ 5.29
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    Current price $ 5.29
  • Original price $ 5.89 - Original price $ 5.89
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    Foster 48-4B, 4 Series, Industrial Plug, 3/8" Hose Barb, Brass

    In stock

    Series: 4 Part Number: 48-4B Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Hose Barb Material: Heavy-Duty Brass Rated Pressure: 30...

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    Original price $ 5.89 - Original price $ 5.89
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    Current price $ 5.89
  • Original price $ 3.99 - Original price $ 3.99
    Original price
    $ 3.99
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    Current price $ 3.99

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

    In stock

    Series: 4 Part Number: 41-4 Interchange: Industrial Body: 3/8" Plug Thread: 1/4" Female NPT, FPT Material: Heavy-Duty Steel Rated Pressur...

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    Original price $ 3.99 - Original price $ 3.99
    Original price
    $ 3.99
    $ 3.99 - $ 3.99
    Current price $ 3.99
  • Original price $ 19.69 - Original price $ 19.69
    Original price
    $ 19.69
    $ 19.69 - $ 19.69
    Current price $ 19.69

    Foster FM4504, 4 Series, Industrial Coupler, Automatic, 1/2" Male NPT, Brass

    In stock

    Series: 4 Part Number: FM4504 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 1/2" Male NPT, MPT Material: Heavy-Duty Brass,...

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    Original price $ 19.69 - Original price $ 19.69
    Original price
    $ 19.69
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    Current price $ 19.69
  • Original price $ 21.19 - Original price $ 21.19
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    Current price $ 21.19

    Foster FM1714, 4 Series, Industrial Coupler, Automatic, 3/8" Push-On Hose Barb, Brass

    In stock

    Series: 4 Part Number: FM1714 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 3/8" Push-On Hose Barb Material: Heavy-Duty Br...

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    Original price $ 21.19 - Original price $ 21.19
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    Current price $ 21.19
  • Original price $ 19.39 - Original price $ 19.39
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    $ 19.39
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    Current price $ 19.39

    Foster FM4004, 4 Series, Industrial Coupler, Automatic, 1/4" Female NPT, Brass

    In stock

    Series: 4 Part Number: FM4004 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 1/4" Female NPT, FPT Material: Heavy-Duty Bras...

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    Original price $ 19.39 - Original price $ 19.39
    Original price
    $ 19.39
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    Current price $ 19.39
  • Original price $ 19.99 - Original price $ 19.99
    Original price
    $ 19.99
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    Current price $ 19.99

    Foster FM4804, 4 Series, Industrial Coupler, Automatic, 3/8" Hose Barb, Brass

    In stock

    Series: 4 Part Number: FM4804 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 3/8" Hose Barb Material: Heavy-Duty Brass, Ste...

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    Original price $ 19.99 - Original price $ 19.99
    Original price
    $ 19.99
    $ 19.99 - $ 19.99
    Current price $ 19.99
  • Original price $ 19.39 - Original price $ 19.39
    Original price
    $ 19.39
    $ 19.39 - $ 19.39
    Current price $ 19.39

    Foster FM4104, 4 Series, Industrial Coupler, Automatic, 1/4" Male NPT, Brass

    In stock

    Series: 4 Part Number: FM4104 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 1/4" Male NPT, MPT Material: Heavy-Duty Brass,...

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    Original price $ 19.39 - Original price $ 19.39
    Original price
    $ 19.39
    $ 19.39 - $ 19.39
    Current price $ 19.39
  • Original price $ 15.29 - Original price $ 15.29
    Original price
    $ 15.29
    $ 15.29 - $ 15.29
    Current price $ 15.29

    Foster 4204, 4 Series, Industrial Coupler, Manual, 3/8" Female NPT, Brass, Steel

    In stock

    Series: 4 Part Number: 4204 Interchange: Industrial, I/M Body: 3/8" Manual Coupler Thread: 3/8" Female NPT, FPT Material: Heavy-Duty Brass...

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    Original price $ 15.29 - Original price $ 15.29
    Original price
    $ 15.29
    $ 15.29 - $ 15.29
    Current price $ 15.29
  • Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59

    Foster 46-4, 4 Series, Industrial Plug, 1/4" Hose Barb, Steel

    In stock

    Series: 4 Part Number: 46-4 Interchange: Industrial Body: 3/8" Plug Thread: 1/4" Hose Barb Material: Heavy-Duty Steel Rated Pressure: 300...

    View full details
    Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59
  • Original price $ 5.09 - Original price $ 5.09
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    $ 5.09
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    Current price $ 5.09

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

    In stock

    Series: 4 Part Number: 44-4 Interchange: Industrial Body: 3/8" Plug Thread: 1/2" Male NPT, MPT Material: Heavy-Duty Steel Rated Pressure:...

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    Original price $ 5.09 - Original price $ 5.09
    Original price
    $ 5.09
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    Current price $ 5.09
  • Original price $ 6.99 - Original price $ 6.99
    Original price
    $ 6.99
    $ 6.99 - $ 6.99
    Current price $ 6.99

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

    In stock

    Series: 4 Part Number: 40-4B Interchange: Industrial Body: 3/8" Plug Thread: 1/4" Male NPT, MPT Material: Heavy-Duty Brass Rated Pressure...

    View full details
    Original price $ 6.99 - Original price $ 6.99
    Original price
    $ 6.99
    $ 6.99 - $ 6.99
    Current price $ 6.99
  • Original price $ 20.19 - Original price $ 20.19
    Original price
    $ 20.19
    $ 20.19 - $ 20.19
    Current price $ 20.19

    Foster FM4904, 4 Series, Industrial Coupler, Automatic, 1/2" Hose Barb, Brass

    In stock

    Series: 4 Part Number: FM4904 Interchange: Industrial Body: 3/8" Coupler, Automatic Thread: 1/2" Hose Barb Material: Heavy-Duty Brass, Ste...

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    Original price $ 20.19 - Original price $ 20.19
    Original price
    $ 20.19
    $ 20.19 - $ 20.19
    Current price $ 20.19
  • Original price $ 14.79 - Original price $ 14.79
    Original price
    $ 14.79
    $ 14.79 - $ 14.79
    Current price $ 14.79

    Foster 4004, 4 Series, Industrial Coupler, Manual, 1/4" Female NPT, Brass, Steel

    In stock

    Series: 4 Part Number: 4004 Interchange: Industrial, I/M Body: 3/8" Manual Coupler Thread: 1/4" Female NPT, FPT Material: Heavy-Duty Brass...

    View full details
    Original price $ 14.79 - Original price $ 14.79
    Original price
    $ 14.79
    $ 14.79 - $ 14.79
    Current price $ 14.79
  • Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59

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

    In stock

    Series: 4 Part Number: 71-4 Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Push-On Hose Barb Material: Heavy-Duty Steel Rated Press...

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    Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59
  • Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59

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

    In stock

    Series: 4 Part Number: 48-4 Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Hose Barb Material: Heavy-Duty Steel Rated Pressure: 300...

    View full details
    Original price $ 4.59 - Original price $ 4.59
    Original price
    $ 4.59
    $ 4.59 - $ 4.59
    Current price $ 4.59
  • Original price $ 5.29 - Original price $ 5.29
    Original price
    $ 5.29
    $ 5.29 - $ 5.29
    Current price $ 5.29

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

    In stock

    Series: 4 Part Number: 42-4B Interchange: Industrial Body: 3/8" Plug Thread: 3/8" Male NPT, MPT Material: Heavy-Duty Brass Rated Pressure...

    View full details
    Original price $ 5.29 - Original price $ 5.29
    Original price
    $ 5.29
    $ 5.29 - $ 5.29
    Current price $ 5.29