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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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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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 BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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 —...

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€9,95 - €9,95
€9,95
€9,95 - €9,95
€9,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95

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

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 — ...

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€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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 —...

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€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€56,95 - €56,95
€56,95
€56,95 - €56,95
€56,95

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

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...

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€56,95 - €56,95
€56,95
€56,95 - €56,95
€56,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€52,95 - €52,95
€52,95
€52,95 - €52,95
€52,95

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

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...

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€52,95 - €52,95
€52,95
€52,95 - €52,95
€52,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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...

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€14,95 - €14,95
€14,95
€14,95 - €14,95
€14,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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...

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€13,95 - €13,95
€13,95
€13,95 - €13,95
€13,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€13,95 - €13,95
€13,95
€13,95 - €13,95
€13,95

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

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
€13,95 - €13,95
€13,95
€13,95 - €13,95
€13,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

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

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...

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€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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...

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€13,95 - €13,95
€13,95
€13,95 - €13,95
€13,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€49,95 - €49,95
€49,95
€49,95 - €49,95
€49,95

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

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...

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€49,95 - €49,95
€49,95
€49,95 - €49,95
€49,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€52,95 - €52,95
€52,95
€52,95 - €52,95
€52,95

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

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...

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€52,95 - €52,95
€52,95
€52,95 - €52,95
€52,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€48,95 - €48,95
€48,95
€48,95 - €48,95
€48,95

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

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
€48,95 - €48,95
€48,95
€48,95 - €48,95
€48,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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 BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

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

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
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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 BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95

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

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
€11,95 - €11,95
€11,95
€11,95 - €11,95
€11,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€17,95 - €17,95
€17,95
€17,95 - €17,95
€17,95

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

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
€17,95 - €17,95
€17,95
€17,95 - €17,95
€17,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€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

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
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€34,95 - €34,95
€34,95
€34,95 - €34,95
€34,95

Foster 3003S/SH, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Heat/Viton, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003S/SH is a 303 Stainless 1/4" industrial coupler from the Foster 3 Seri...

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€34,95 - €34,95
€34,95
€34,95 - €34,95
€34,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€36,95 - €36,95
€36,95
€36,95 - €36,95
€36,95

Foster BL3003S/S, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

View full details
€36,95 - €36,95
€36,95
€36,95 - €36,95
€36,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€32,95 - €32,95
€32,95
€32,95 - €32,95
€32,95

Foster 3003S/S, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3003S/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

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