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Foster 3 Series Couplers

The Foster 3 Series is the 1/4" body industrial interchange, the most popular air coupler size for shop and industrial systems. This collection includes 3 Series couplers and plugs in brass, steel, and stainless with NPT, hose barb, push-on, and reusable terminations, plus automatic, sleeve guard, ball check, and dust cap options. Filter by thread, material, and coupler or plug to match your line.

  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €34,95 - €34,95
    €34,95
    €34,95 - €34,95
    €34,95

    Foster BL3103S/S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Ball Lock, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3103S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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    €34,95 - €34,95
    €34,95
    €34,95 - €34,95
    €34,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €32,95 - €32,95
    €32,95
    €32,95 - €32,95
    €32,95

    Foster 3103S/S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

    View full details
    €32,95 - €32,95
    €32,95
    €32,95 - €32,95
    €32,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95

    Foster 3103S, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Steam/EPDM, Brass/SS

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €9,95 - €9,95
    €9,95
    €9,95 - €9,95
    €9,95

    Foster 3103LV, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Less Valve, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103LV is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

    View full details
    €9,95 - €9,95
    €9,95
    €9,95 - €9,95
    €9,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95

    Foster 3103H, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Heat/Viton, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103H is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

    View full details
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95

    Foster 3103D, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Dill Valve, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103D is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

    View full details
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95

    Foster BL3103, 1/4" Industrial Coupler x 1/4" Male NPT, 3 Series, Ball Lock, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3103 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

    View full details
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €9,95 - €9,95
    €9,95
    €9,95 - €9,95
    €9,95

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

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3103 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

    View full details
    €9,95 - €9,95
    €9,95
    €9,95 - €9,95
    €9,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €55,95 - €55,95
    €55,95
    €55,95 - €55,95
    €55,95

    Foster BL2903S/S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Ball Lock, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2903S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

    View full details
    €55,95 - €55,95
    €55,95
    €55,95 - €55,95
    €55,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €51,95 - €51,95
    €51,95
    €51,95 - €51,95
    €51,95

    Foster 2903S/S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

    View full details
    €51,95 - €51,95
    €51,95
    €51,95 - €51,95
    €51,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €14,95 - €14,95
    €14,95
    €14,95 - €14,95
    €14,95

    Foster 2903S, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Steam/EPDM, Brass/SS

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

    View full details
    €14,95 - €14,95
    €14,95
    €14,95 - €14,95
    €14,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95

    Foster 2903H, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Heat/Viton, Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

    View full details
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95

    Foster BL2903, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Ball Lock, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2903 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

    View full details
    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95

    Foster 2903, 1/4" Industrial Coupler x 1/8" Male NPT, 3 Series, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2903 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

    View full details
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95

    Foster 3203W, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Water, Brass/SS

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

    View full details
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €48,95 - €48,95
    €48,95
    €48,95 - €48,95
    €48,95

    Foster 3203S/SLV, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Less Valve, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203S/SLV is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

    View full details
    €48,95 - €48,95
    €48,95
    €48,95 - €48,95
    €48,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €51,95 - €51,95
    €51,95
    €51,95 - €51,95
    €51,95

    Foster BL3203S/S, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Ball Lock, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3203S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

    View full details
    €51,95 - €51,95
    €51,95
    €51,95 - €51,95
    €51,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €47,95 - €47,95
    €47,95
    €47,95 - €47,95
    €47,95

    Foster 3203S/S, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, 303 Stainless

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

    View full details
    €47,95 - €47,95
    €47,95
    €47,95 - €47,95
    €47,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95

    Foster 3203LV, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Less Valve, Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203LV is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

    View full details
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95

    Foster 3203H, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Heat/Viton, Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

    View full details
    €11,95 - €11,95
    €11,95
    €11,95 - €11,95
    €11,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95

    Foster BL3203, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Ball Lock, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3203 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

    View full details
    €12,95 - €12,95
    €12,95
    €12,95 - €12,95
    €12,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95

    Foster 3203, 1/4" Industrial Coupler x 3/8" Female NPT, 3 Series, Brass/Steel

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3203 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

    View full details
    €10,95 - €10,95
    €10,95
    €10,95 - €10,95
    €10,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €16,95 - €16,95
    €16,95
    €16,95 - €16,95
    €16,95

    Foster BL3003W, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, Water, Brass/SS

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — t...

    View full details
    €16,95 - €16,95
    €16,95
    €16,95 - €16,95
    €16,95
  • Foster 3PDC, 1/4" 3 Series Plug Dust Cap, Plastic
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95

    Foster 3003W, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Water, Brass/SS

    In stock

    Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

    View full details
    €13,95 - €13,95
    €13,95
    €13,95 - €13,95
    €13,95