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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.

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€1,95 - €1,95
€1,95
€1,95 - €1,95
€1,95

Foster 10-3, 3 Series, Industrial Plug, 1/4" Male NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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€1,95 - €1,95
€1,95
€1,95 - €1,95
€1,95
€10,95 - €10,95
€10,95
€10,95 - €10,95
€10,95

Foster 3003, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, Brass, Steel

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

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€10,95 - €10,95
€10,95
€10,95 - €10,95
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€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

Foster 10-3B, 3 Series, Industrial Plug, 1/4" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 10-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95
€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95

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

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...

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€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95
€1,95 - €1,95
€1,95
€1,95 - €1,95
€1,95

Foster 11-3, 3 Series, Industrial Plug, 1/4" Female NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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€1,95 - €1,95
€1,95
€1,95 - €1,95
€1,95
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

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

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 12-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

Foster 16-3, 3 Series, Industrial Plug, 1/4" Hose Barb, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 16-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95
€3,95 - €3,95
€3,95
€3,95 - €3,95
€3,95

Foster 11-3B, 3 Series, Industrial Plug, 1/4" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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€3,95 - €3,95
€3,95
€3,95 - €3,95
€3,95
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95

Foster FM3103, 3 Series, Industrial Coupler, Automatic, 1/4" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3103 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95
€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95

Foster 3003GB, 3 Series, Industrial Coupler, Automatic, 1/4" Female NPT, Brass

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

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€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95
€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95

Foster SG3103, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3103 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95
€3,95 - €3,95
€3,95
€3,95 - €3,95
€3,95

Foster 13-3B, 3 Series, Industrial Plug, 1/8" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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€3,95 - €3,95
€3,95
€3,95 - €3,95
€3,95
€5,95 - €5,95
€5,95
€5,95 - €5,95
€5,95

Foster 17-3B, 3 Series, Industrial Plug, 3/8" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 17-3B is a Brass 1/4" industrial plug from the Foster 3 Series — the most ...

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€5,95 - €5,95
€5,95
€5,95 - €5,95
€5,95
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95

Foster 3003GS, 3 Series, Industrial Coupler, Automatic, 1/4" Female NPT, Brass, Steel

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

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€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

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

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 17-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95
€10,95 - €10,95
€10,95
€10,95 - €10,95
€10,95

Foster 3603, 3 Series, Industrial Coupler, Manual, 1/4" Hose Barb, Brass, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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€10,95 - €10,95
€10,95
€10,95 - €10,95
€10,95
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95

Foster FM3203, 3 Series, Industrial Coupler, Automatic, 3/8" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3203 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95
€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95

Foster SG3003, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Female NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3003 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95
€10,95 - €10,95
€10,95
€10,95 - €10,95
€10,95

Foster 3303, 3 Series, Industrial Coupler, Manual, 3/8" Male NPT, Brass, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3303 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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€10,95 - €10,95
€10,95
€10,95 - €10,95
€10,95
€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95

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

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

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€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95
€14,95 - €14,95
€14,95
€14,95 - €14,95
€14,95

Foster 3003HW, 3 Series, Industrial Coupler, Manual, 1/4" Female NPT, Brass (HOT WATER)

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

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€14,95 - €14,95
€14,95
€14,95 - €14,95
€14,95
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95

Foster FM3303, 3 Series, Industrial Coupler, Automatic, 3/8" Male NPT, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster FM3303 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

View full details
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95
€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95

Foster SG3603, 3 Series, Industrial Coupler, Manual, Sleeve Guard, 1/4" Hose Barb, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SG3603 is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

View full details
€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

Foster 13-3, 3 Series, Industrial Plug, 1/8" Female NPT, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

View full details
€2,95 - €2,95
€2,95
€2,95 - €2,95
€2,95

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