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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 Save 20% Save %
$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00

Foster 12-3B, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, Brass

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

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$ 95.00
$ 95.00 - $ 95.00
$ 95.00
$ 76.00
$ 76.00 - $ 76.00
$ 76.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 55.00
$ 55.00 - $ 55.00
$ 55.00
$ 44.00
$ 44.00 - $ 44.00
$ 44.00

Foster 12-3, 1/4" Industrial Plug x 1/8" Male NPT, 3 Series, 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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$ 55.00
$ 55.00 - $ 55.00
$ 55.00
$ 44.00
$ 44.00 - $ 44.00
$ 44.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 21% Save %
$ 110.00
$ 110.00 - $ 110.00
$ 110.00
$ 87.00
$ 87.00 - $ 87.00
$ 87.00

Foster 15-3, 1/4" Industrial Plug x 3/8" Female NPT, 3 Series, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 15-3 is a Steel 1/4" industrial plug from the Foster 3 Series — the most p...

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$ 110.00
$ 110.00 - $ 110.00
$ 110.00
$ 87.00
$ 87.00 - $ 87.00
$ 87.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass Save 20% Save %
$ 216.00
$ 216.00 - $ 216.00
$ 216.00
$ 172.00
$ 172.00 - $ 172.00
$ 172.00

Foster 11-3S/S, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 11-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 216.00
$ 216.00 - $ 216.00
$ 216.00
$ 172.00
$ 172.00 - $ 172.00
$ 172.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 21% Save %
$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00

Foster 11-3B, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, 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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$ 91.00
$ 91.00 - $ 91.00
$ 91.00
$ 72.00
$ 72.00 - $ 72.00
$ 72.00
Save 21% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 18% Save %
$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 42.00
$ 42.00 - $ 42.00
$ 42.00

Foster 11-3, 1/4" Industrial Plug x 1/4" Female NPT, 3 Series, 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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$ 51.00
$ 51.00 - $ 51.00
$ 51.00
$ 42.00
$ 42.00 - $ 42.00
$ 42.00
Save 18% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 644.00
$ 644.00 - $ 644.00
$ 644.00
$ 516.00
$ 516.00 - $ 516.00
$ 516.00

Foster 13-3S/S, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 13-3S/S is a 303 Stainless 1/4" industrial plug from the Foster 3 Series —...

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$ 644.00
$ 644.00 - $ 644.00
$ 644.00
$ 516.00
$ 516.00 - $ 516.00
$ 516.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 106.00
$ 106.00 - $ 106.00
$ 106.00
$ 85.00
$ 85.00 - $ 85.00
$ 85.00

Foster 13-3B, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, 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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$ 106.00
$ 106.00 - $ 106.00
$ 106.00
$ 85.00
$ 85.00 - $ 85.00
$ 85.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 22% Save %
$ 63.00
$ 63.00 - $ 63.00
$ 63.00
$ 49.00
$ 49.00 - $ 49.00
$ 49.00

Foster 13-3, 1/4" Industrial Plug x 1/8" Female NPT, 3 Series, 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...

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$ 63.00
$ 63.00 - $ 63.00
$ 63.00
$ 49.00
$ 49.00 - $ 49.00
$ 49.00
Save 22% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 525.00
$ 525.00 - $ 525.00
$ 525.00
$ 421.00
$ 421.00 - $ 421.00
$ 421.00

Foster SD11-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD11-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the...

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$ 525.00
$ 525.00 - $ 525.00
$ 525.00
$ 421.00
$ 421.00 - $ 421.00
$ 421.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 688.00
$ 688.00 - $ 688.00
$ 688.00
$ 550.00
$ 550.00 - $ 550.00
$ 550.00

Foster SD11-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 3/4" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD11-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the...

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$ 688.00
$ 688.00 - $ 688.00
$ 688.00
$ 550.00
$ 550.00 - $ 550.00
$ 550.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 510.00
$ 510.00 - $ 510.00
$ 510.00
$ 408.00
$ 408.00 - $ 408.00
$ 408.00

Foster SD7-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD7-3GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 510.00
$ 510.00 - $ 510.00
$ 510.00
$ 408.00
$ 408.00 - $ 408.00
$ 408.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 608.00
$ 608.00 - $ 608.00
$ 608.00
$ 487.00
$ 487.00 - $ 487.00
$ 487.00

Foster SD7-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 3/8" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster SD7-3GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the ...

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$ 608.00
$ 608.00 - $ 608.00
$ 608.00
$ 487.00
$ 487.00 - $ 487.00
$ 487.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 506.00
$ 506.00 - $ 506.00
$ 506.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00

Foster SB7-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Steel

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

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$ 506.00
$ 506.00 - $ 506.00
$ 506.00
$ 406.00
$ 406.00 - $ 406.00
$ 406.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 631.00
$ 631.00 - $ 631.00
$ 631.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00

Foster SB7-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 5/8" OD, 3 Series, Automatic Slim Profile, Brass

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

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$ 631.00
$ 631.00 - $ 631.00
$ 631.00
$ 506.00
$ 506.00 - $ 506.00
$ 506.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 533.00
$ 533.00 - $ 533.00
$ 533.00
$ 427.00
$ 427.00 - $ 427.00
$ 427.00

Foster SB5-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Automatic Slim Profile, Steel

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

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$ 533.00
$ 533.00 - $ 533.00
$ 533.00
$ 427.00
$ 427.00 - $ 427.00
$ 427.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 688.00
$ 688.00 - $ 688.00
$ 688.00
$ 550.00
$ 550.00 - $ 550.00
$ 550.00

Foster SB5-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 9/16" OD, 3 Series, Automatic Slim Profile, Brass

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

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$ 688.00
$ 688.00 - $ 688.00
$ 688.00
$ 550.00
$ 550.00 - $ 550.00
$ 550.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 497.00
$ 497.00 - $ 497.00
$ 497.00
$ 397.00
$ 397.00 - $ 397.00
$ 397.00

Foster SB3-3GS, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic Slim Profile, Steel

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

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$ 497.00
$ 497.00 - $ 497.00
$ 497.00
$ 397.00
$ 397.00 - $ 397.00
$ 397.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 623.00
$ 623.00 - $ 623.00
$ 623.00
$ 499.00
$ 499.00 - $ 499.00
$ 499.00

Foster SB3-3GB, 1/4" Industrial Coupler x Reusable Hose Fitting, 1/4" ID x 1/2" OD, 3 Series, Automatic Slim Profile, Brass

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

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$ 623.00
$ 623.00 - $ 623.00
$ 623.00
$ 499.00
$ 499.00 - $ 499.00
$ 499.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 550.00
$ 550.00 - $ 550.00
$ 550.00
$ 440.00
$ 440.00 - $ 440.00
$ 440.00

Foster 1713GB, 1/4" Industrial Coupler x 3/8" Push-On Hose Stem, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1713GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 550.00
$ 550.00 - $ 550.00
$ 550.00
$ 440.00
$ 440.00 - $ 440.00
$ 440.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 588.00
$ 588.00 - $ 588.00
$ 588.00
$ 470.00
$ 470.00 - $ 470.00
$ 470.00

Foster 1513GB, 1/4" Industrial Coupler x 1/4" Push-On Hose Stem, 3 Series, Automatic Slim Profile, Brass

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 1513GB is a Brass 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 588.00
$ 588.00 - $ 588.00
$ 588.00
$ 470.00
$ 470.00 - $ 470.00
$ 470.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 429.00
$ 429.00 - $ 429.00
$ 429.00
$ 344.00
$ 344.00 - $ 344.00
$ 344.00

Foster 3703GS, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic Slim Profile, Steel

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

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$ 429.00
$ 429.00 - $ 429.00
$ 429.00
$ 344.00
$ 344.00 - $ 344.00
$ 344.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 561.00
$ 561.00 - $ 561.00
$ 561.00
$ 448.00
$ 448.00 - $ 448.00
$ 448.00

Foster 3703GB, 1/4" Industrial Coupler x 3/8" Hose ID, 3 Series, Automatic Slim Profile, Brass

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

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$ 561.00
$ 561.00 - $ 561.00
$ 561.00
$ 448.00
$ 448.00 - $ 448.00
$ 448.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
Save 20% Save %
$ 525.00
$ 525.00 - $ 525.00
$ 525.00
$ 420.00
$ 420.00 - $ 420.00
$ 420.00

Foster 3653GS, 1/4" Industrial Coupler x 5/16" Hose ID, 3 Series, Automatic Slim Profile, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 3653GS is a Steel 1/4" industrial coupler from the Foster 3 Series — the m...

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$ 525.00
$ 525.00 - $ 525.00
$ 525.00
$ 420.00
$ 420.00 - $ 420.00
$ 420.00
Save 20% Save %

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