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🔧 Spring Savings Are Here – Get Up to 30% Off Select Fittings & Hose!
🔧 Spring Savings Are Here – Get Up to 30% Off Select Fittings & Hose!

ZSI Foster - 3 Series, 1/4" Body Industrial Interchange Pneumatic Couplers and Plugs

ZSI Foster's "3 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 1/4" industrial interchange compatibility means they can be used with fittings from other manufacturers. With their reliability and versatility, the "3 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 $ 11.69
    Original price $ 11.69 - Original price $ 11.69
    Original price $ 11.69
    Current price $ 8.18
    $ 8.18 - $ 8.18
    Current price $ 8.18

    Foster SG3703, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 3/8" Hose Barb, Brass

    In stock

    Series: 3 Part Number: SG3703 Interchange: Industrial, I/M Body: 1/4" Coupler, Manual, Sleeve Guard Thread: 3/8" Hose Barb Material: Heavy...

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    Original price $ 11.69
    Original price $ 11.69 - Original price $ 11.69
    Original price $ 11.69
    Current price $ 8.18
    $ 8.18 - $ 8.18
    Current price $ 8.18
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  • Original price $ 19.49
    Original price $ 19.49 - Original price $ 19.49
    Original price $ 19.49
    Current price $ 13.64
    $ 13.64 - $ 13.64
    Current price $ 13.64

    Foster FM3603, 3 Series, Industrial Coupler, Automatic, 1/4" Hose Barb, Brass

    In stock

    Series: 3 Part Number: FM3603 Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/4" Hose Barb Material: Heavy-Duty Brass...

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    Original price $ 19.49
    Original price $ 19.49 - Original price $ 19.49
    Original price $ 19.49
    Current price $ 13.64
    $ 13.64 - $ 13.64
    Current price $ 13.64
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  • Original price $ 13.19
    Original price $ 13.19 - Original price $ 13.19
    Original price $ 13.19
    Current price $ 9.23
    $ 9.23 - $ 9.23
    Current price $ 9.23

    Foster 3203, 3 Series, Industrial Coupler, Manual, 3/8" Female NPT, Brass, Steel

    In stock

    Series: 3 Part Number: 3203 Interchange: Industrial, I/M Body: 1/4" Coupler, Manual Thread: 3/8" Female NPT, FPT Material: Heavy-Duty Bras...

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    Original price $ 13.19
    Original price $ 13.19 - Original price $ 13.19
    Original price $ 13.19
    Current price $ 9.23
    $ 9.23 - $ 9.23
    Current price $ 9.23
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  • Original price $ 8.19
    Original price $ 8.19 - Original price $ 8.19
    Original price $ 8.19
    Current price $ 5.73
    $ 5.73 - $ 5.73
    Current price $ 5.73

    Foster 165-3, 3 Series, Industrial Plug, 5/16" Hose Barb, Steel

    In stock

    Series: 3 Part Number: 165-3 Interchange: Industrial Body: 1/4" Plug Thread: 5/16" Hose Barb Material: Heavy-Duty Steel Rated Pressure: ...

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    Original price $ 8.19
    Original price $ 8.19 - Original price $ 8.19
    Original price $ 8.19
    Current price $ 5.73
    $ 5.73 - $ 5.73
    Current price $ 5.73
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  • Original price $ 3.69
    Original price $ 3.69 - Original price $ 3.69
    Original price $ 3.69
    Current price $ 2.58
    $ 2.58 - $ 2.58
    Current price $ 2.58

    Foster 14-3, 3 Series, Industrial Plug, 3/8" Male NPT, Steel

    In stock

    Series: 3 Part Number: 14-3 Interchange: Industrial Body: 1/4" 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
    Original price $ 3.69
    Current price $ 2.58
    $ 2.58 - $ 2.58
    Current price $ 2.58
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  • Original price $ 35.79
    Original price $ 35.79 - Original price $ 35.79
    Original price $ 35.79
    Current price $ 25.05
    $ 25.05 - $ 25.05
    Current price $ 25.05

    Foster SV3103, 3 Series, Industrial Coupler, Manual, 1/4" Male NPT, Safety Valve, Brass, Steel

    In stock

    Series: 3 Part Number: SV3103 Interchange: Industrial, I/M Body: 1/4" Coupler, Manual, Safety Valve Thread: 1/4" Male NPT, MPT Material: H...

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    Original price $ 35.79
    Original price $ 35.79 - Original price $ 35.79
    Original price $ 35.79
    Current price $ 25.05
    $ 25.05 - $ 25.05
    Current price $ 25.05
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  • Original price $ 35.79
    Original price $ 35.79 - Original price $ 35.79
    Original price $ 35.79
    Current price $ 25.05
    $ 25.05 - $ 25.05
    Current price $ 25.05

    Foster SV3003, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, Safety Valve, Brass, Steel

    In stock

    Series: 3 Part Number: SV3003 Interchange: Industrial, I/M Body: 1/4" Coupler, Manual, Safety Valve Thread: 1/4" Female NPT, FPT Material:...

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    Original price $ 35.79
    Original price $ 35.79 - Original price $ 35.79
    Original price $ 35.79
    Current price $ 25.05
    $ 25.05 - $ 25.05
    Current price $ 25.05
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  • Original price $ 24.89
    Original price $ 24.89 - Original price $ 24.89
    Original price $ 24.89
    Current price $ 17.42
    $ 17.42 - $ 17.42
    Current price $ 17.42

    Foster 1713GB, 3 Series, Industrial Coupler, Automatic, 3/8" Hose Barb (Push-On), Brass

    In stock

    Series: 3 Part Number: 1713GB Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 3/8" Hose Barb (Push-On) Material: Heavy-...

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    Original price $ 24.89
    Original price $ 24.89 - Original price $ 24.89
    Original price $ 24.89
    Current price $ 17.42
    $ 17.42 - $ 17.42
    Current price $ 17.42
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  • Original price $ 26.59
    Original price $ 26.59 - Original price $ 26.59
    Original price $ 26.59
    Current price $ 18.61
    $ 18.61 - $ 18.61
    Current price $ 18.61

    Foster 1513GB, 3 Series, Industrial Coupler, Automatic, 1/4" Hose Barb (Push-On), Brass

    In stock

    Series: 3 Part Number: 1513GB Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/4" Hose Barb (Push-On) Material: Heavy-...

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    Original price $ 26.59
    Original price $ 26.59 - Original price $ 26.59
    Original price $ 26.59
    Current price $ 18.61
    $ 18.61 - $ 18.61
    Current price $ 18.61
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  • Original price $ 24.29
    Original price $ 24.29 - Original price $ 24.29
    Original price $ 24.29
    Current price $ 17.00
    $ 17.00 - $ 17.00
    Current price $ 17.00

    Foster 3653GB, 3 Series, Industrial Coupler, Automatic, 5/16" Hose Barb, Brass

    In stock

    Series: 3 Part Number: 3653GB Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 5/16" Hose Barb Material: Heavy-Duty Bras...

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    Original price $ 24.29
    Original price $ 24.29 - Original price $ 24.29
    Original price $ 24.29
    Current price $ 17.00
    $ 17.00 - $ 17.00
    Current price $ 17.00
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  • Original price $ 24.09
    Original price $ 24.09 - Original price $ 24.09
    Original price $ 24.09
    Current price $ 16.86
    $ 16.86 - $ 16.86
    Current price $ 16.86

    Foster 3303GB, 3 Series, Industrial Coupler, Automatic, 3/8" Male NPT, Brass

    In stock

    Series: 3 Part Number: 3303GB Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 3/8" Male NPT, FPT Material: Heavy-Duty B...

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    Original price $ 24.09
    Original price $ 24.09 - Original price $ 24.09
    Original price $ 24.09
    Current price $ 16.86
    $ 16.86 - $ 16.86
    Current price $ 16.86
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  • Original price $ 31.49
    Original price $ 31.49 - Original price $ 31.49
    Original price $ 31.49
    Current price $ 22.04
    $ 22.04 - $ 22.04
    Current price $ 22.04

    Foster 2903GB, 3 Series, Industrial Coupler, Automatic, 1/8" Male NPT, Brass

    In stock

    Series: 3 Part Number: 2903GB Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/8" Male NPT, FPT Material: Heavy-Duty B...

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    Original price $ 31.49
    Original price $ 31.49 - Original price $ 31.49
    Original price $ 31.49
    Current price $ 22.04
    $ 22.04 - $ 22.04
    Current price $ 22.04
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  • Original price $ 21.89
    Original price $ 21.89 - Original price $ 21.89
    Original price $ 21.89
    Current price $ 15.32
    $ 15.32 - $ 15.32
    Current price $ 15.32

    Foster 3703GS, 3 Series, Industrial Coupler, Automatic, 3/8" Hose Barb, Brass, Steel

    In stock

    Series: 3 Part Number: 3703GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 3/8" Hose Barb Material: Heavy-Duty Brass...

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    Original price $ 21.89
    Original price $ 21.89 - Original price $ 21.89
    Original price $ 21.89
    Current price $ 15.32
    $ 15.32 - $ 15.32
    Current price $ 15.32
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  • Original price $ 26.69
    Original price $ 26.69 - Original price $ 26.69
    Original price $ 26.69
    Current price $ 18.68
    $ 18.68 - $ 18.68
    Current price $ 18.68

    Foster 3653GS, 3 Series, Industrial Coupler, Automatic, 5/16" Hose Barb, Brass, Steel

    In stock

    Series: 3 Part Number: 3653GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 5/16" Hose Barb Material: Heavy-Duty Bras...

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    Original price $ 26.69
    Original price $ 26.69 - Original price $ 26.69
    Original price $ 26.69
    Current price $ 18.68
    $ 18.68 - $ 18.68
    Current price $ 18.68
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  • Original price $ 21.79
    Original price $ 21.79 - Original price $ 21.79
    Original price $ 21.79
    Current price $ 15.25
    $ 15.25 - $ 15.25
    Current price $ 15.25

    Foster 3203GS, 3 Series, Industrial Coupler, Automatic, 3/8" Female NPT, Brass, Steel

    In stock

    Series: 3 Part Number: 3203GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 3/8" Female NPT, FPT Material: Heavy-Duty...

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    Original price $ 21.79
    Original price $ 21.79 - Original price $ 21.79
    Original price $ 21.79
    Current price $ 15.25
    $ 15.25 - $ 15.25
    Current price $ 15.25
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  • Original price $ 20.79
    Original price $ 20.79 - Original price $ 20.79
    Original price $ 20.79
    Current price $ 14.55
    $ 14.55 - $ 14.55
    Current price $ 14.55

    Foster 3103GS, 3 Series, Industrial Coupler, Automatic, 1/4" Male NPT, Brass, Steel

    In stock

    Series: 3 Part Number: 3103GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/4" Male NPT, MPT Material: Heavy-Duty B...

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    Original price $ 20.79
    Original price $ 20.79 - Original price $ 20.79
    Original price $ 20.79
    Current price $ 14.55
    $ 14.55 - $ 14.55
    Current price $ 14.55
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  • Original price $ 14.29
    Original price $ 14.29 - Original price $ 14.29
    Original price $ 14.29
    Current price $ 10.00
    $ 10.00 - $ 10.00
    Current price $ 10.00

    Foster 2903GS, 3 Series, Industrial Coupler, Automatic, 1/8" Male NPT, Brass, Steel

    In stock

    Series: 3 Part Number: 2903GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/8" Male NPT, MPT Material: Heavy-Duty B...

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    Original price $ 14.29
    Original price $ 14.29 - Original price $ 14.29
    Original price $ 14.29
    Current price $ 10.00
    $ 10.00 - $ 10.00
    Current price $ 10.00
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  • Original price $ 28.59
    Original price $ 28.59 - Original price $ 28.59
    Original price $ 28.59
    Current price $ 20.01
    $ 20.01 - $ 20.01
    Current price $ 20.01

    Foster 2803GS, 3 Series, Industrial Coupler, Automatic, 1/8" Female NPT, Brass, Steel

    In stock

    Series: 3 Part Number: 2803GS Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 1/8" Female NPT, FPT Material: Heavy-Dut...

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    Original price $ 28.59
    Original price $ 28.59 - Original price $ 28.59
    Original price $ 28.59
    Current price $ 20.01
    $ 20.01 - $ 20.01
    Current price $ 20.01
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  • Original price $ 19.89
    Original price $ 19.89 - Original price $ 19.89
    Original price $ 19.89
    Current price $ 13.92
    $ 13.92 - $ 13.92
    Current price $ 13.92

    Foster FM3653, 3 Series, Industrial Coupler, Automatic, 5/16" Hose Barb, Brass

    In stock

    Series: 3 Part Number: FM3653 Interchange: Industrial, I/M Body: 1/4" Coupler, Automatic Thread: 5/16" Hose Barb Material: Heavy-Duty Bras...

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    Original price $ 19.89
    Original price $ 19.89 - Original price $ 19.89
    Original price $ 19.89
    Current price $ 13.92
    $ 13.92 - $ 13.92
    Current price $ 13.92
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  • Original price $ 66.09
    Original price $ 66.09 - Original price $ 66.09
    Original price $ 66.09
    Current price $ 46.26
    $ 46.26 - $ 46.26
    Current price $ 46.26

    Foster 3703S/S, 3 Series, Industrial Coupler, Manual, 3/8" Hose Barb, Stainless Steel

    In stock

    Series: 3 Part Number: 3703S/S Interchange: Industrial, I/M Body: 1/4" Coupler, Manual Thread: 3/8" Hose Barb Material: Stainless Steel ...

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    Original price $ 66.09
    Original price $ 66.09 - Original price $ 66.09
    Original price $ 66.09
    Current price $ 46.26
    $ 46.26 - $ 46.26
    Current price $ 46.26
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  • Original price $ 63.79
    Original price $ 63.79 - Original price $ 63.79
    Original price $ 63.79
    Current price $ 44.65
    $ 44.65 - $ 44.65
    Current price $ 44.65

    Foster 3203S/S, 3 Series, Industrial Coupler, Manual, 3/8" Female NPT, Stainless Steel

    In stock

    Series: 3 Part Number: 3203S/S Interchange: Industrial, I/M Body: 1/4" Coupler, Manual Thread: 3/8" Female NPT, FPT Material: 303 Stainles...

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    Original price $ 63.79
    Original price $ 63.79 - Original price $ 63.79
    Original price $ 63.79
    Current price $ 44.65
    $ 44.65 - $ 44.65
    Current price $ 44.65
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  • Original price $ 26.39
    Original price $ 26.39 - Original price $ 26.39
    Original price $ 26.39
    Current price $ 18.47
    $ 18.47 - $ 18.47
    Current price $ 18.47

    Foster 14S-3, 3 Series, Industrial Swivel Plug, 3/8" Male NPT, Steel, Brass

    In stock

    Series: 3 Part Number: 14S-3 Interchange: Industrial Body: 1/4" Swivel Plug Thread: 3/8" Male NPT, MPT Material: Heavy-Duty Steel, Brass ...

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    Original price $ 26.39
    Original price $ 26.39 - Original price $ 26.39
    Original price $ 26.39
    Current price $ 18.47
    $ 18.47 - $ 18.47
    Current price $ 18.47
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  • Original price $ 9.49
    Original price $ 9.49 - Original price $ 9.49
    Original price $ 9.49
    Current price $ 6.64
    $ 6.64 - $ 6.64
    Current price $ 6.64

    Foster 12S-3, 3 Series, Industrial Swivel Plug, 1/8" Male NPT, Steel, Brass

    In stock

    Series: 3 Part Number: 12S-3 Interchange: Industrial Body: 1/4" Swivel Plug Thread: 1/8" Male NPT, MPT Material: Heavy-Duty Steel, Brass ...

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    Original price $ 9.49
    Original price $ 9.49 - Original price $ 9.49
    Original price $ 9.49
    Current price $ 6.64
    $ 6.64 - $ 6.64
    Current price $ 6.64
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  • Original price $ 42.79
    Original price $ 42.79 - Original price $ 42.79
    Original price $ 42.79
    Current price $ 29.95
    $ 29.95 - $ 29.95
    Current price $ 29.95

    Foster 17-3S/S, 3 Series, Industrial Plug, 3/8" Hose Barb, Stainless Steel

    In stock

    Series: 3 Part Number: 17-3S/S Interchange: Industrial Body: 1/4" Plug Thread: 3/8" Hose Barb Material: 303 Stainless Steel Rated Press...

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    Original price $ 42.79
    Original price $ 42.79 - Original price $ 42.79
    Original price $ 42.79
    Current price $ 29.95
    $ 29.95 - $ 29.95
    Current price $ 29.95
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