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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
€23,95 - €23,95
€23,95
€23,95 - €23,95
€23,95

Foster SC7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 5/8" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SC7-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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€23,95 - €23,95
€23,95
€23,95 - €23,95
€23,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€22,95 - €22,95
€22,95
€22,95 - €22,95
€22,95

Foster BLSC5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 9/16" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSC5-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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€22,95 - €22,95
€22,95
€22,95 - €22,95
€22,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€22,95 - €22,95
€22,95
€22,95 - €22,95
€22,95

Foster SC5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 5/16" ID x 9/16" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SC5-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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€22,95 - €22,95
€22,95
€22,95 - €22,95
€22,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€18,95 - €18,95
€18,95
€18,95 - €18,95
€18,95

Foster BLSB7-3W, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Ball Lock, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB7-3W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — ...

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€18,95 - €18,95
€18,95
€18,95 - €18,95
€18,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95

Foster SB7-3W, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB7-3W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — th...

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€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€47,95 - €47,95
€47,95
€47,95 - €47,95
€47,95

Foster BLSB7-3S/S, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB7-3S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Se...

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€47,95 - €47,95
€47,95
€47,95 - €47,95
€47,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€44,95 - €44,95
€44,95
€44,95 - €44,95
€44,95

Foster SB7-3S/S, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB7-3S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Seri...

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€44,95 - €44,95
€44,95
€44,95 - €44,95
€44,95
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 BLSB7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB7-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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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 SB7-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB7-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

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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
€19,95 - €19,95
€19,95
€19,95 - €19,95
€19,95

Foster BLSB5-3W, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Ball Lock, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB5-3W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — ...

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€19,95 - €19,95
€19,95
€19,95 - €19,95
€19,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95

Foster BLSB5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB5-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series ...

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€15,95 - €15,95
€15,95
€15,95 - €15,95
€15,95
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 SB5-3, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB5-3 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — ...

View full details
€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
€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95

Foster SB3-3W, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB3-3W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — th...

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€16,95 - €16,95
€16,95
€16,95 - €16,95
€16,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€77,95 - €77,95
€77,95
€77,95 - €77,95
€77,95

Foster SB3-3S/S, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SB3-3S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Seri...

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€77,95 - €77,95
€77,95
€77,95 - €77,95
€77,95
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
€18,95 - €18,95
€18,95
€18,95 - €18,95
€18,95

Foster BLSB3-3W, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Ball Lock, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BLSB3-3W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — ...

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€18,95 - €18,95
€18,95
€18,95 - €18,95
€18,95
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 3703W, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703W 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
€50,95 - €50,95
€50,95
€50,95 - €50,95
€50,95

Foster BL3703S/S, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Ball Lock, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3703S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Ser...

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€50,95 - €50,95
€50,95
€50,95 - €50,95
€50,95
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 3703S/S, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703S/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
€13,95 - €13,95
€13,95
€13,95 - €13,95
€13,95

Foster 3703S, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3703S 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
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

Foster BL3703, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3703 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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

Foster 3703, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, 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...

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
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

Foster BL3653, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3653 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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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
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

Foster 3653, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3653 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
€12,95 - €12,95
€12,95
€12,95 - €12,95
€12,95

Foster 3603W, 1/4" Industrial Coupler x 1/4" Hose ID, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3603W 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

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