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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 %
$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.29
$ 11.29 - $ 11.29
$ 11.29

Foster 3003LV, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Less Valve, Steel

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

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$ 14.09
$ 14.09 - $ 14.09
$ 14.09
$ 11.29
$ 11.29 - $ 11.29
$ 11.29
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 %
$ 19.89
$ 19.89 - $ 19.89
$ 19.89
$ 15.89
$ 15.89 - $ 15.89
$ 15.89

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

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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$ 19.89
$ 19.89 - $ 19.89
$ 19.89
$ 15.89
$ 15.89 - $ 15.89
$ 15.89
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 %
$ 16.69
$ 16.69 - $ 16.69
$ 16.69
$ 13.29
$ 13.29 - $ 13.29
$ 13.29

Foster 3003H, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Heat/Viton, Steel

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

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$ 16.69
$ 16.69 - $ 16.69
$ 16.69
$ 13.29
$ 13.29 - $ 13.29
$ 13.29
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 %
$ 15.89
$ 15.89 - $ 15.89
$ 15.89
$ 12.69
$ 12.69 - $ 12.69
$ 12.69

Foster 3003D, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Dill Valve, Brass/Steel

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

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$ 15.89
$ 15.89 - $ 15.89
$ 15.89
$ 12.69
$ 12.69 - $ 12.69
$ 12.69
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 %
$ 17.89
$ 17.89 - $ 17.89
$ 17.89
$ 14.29
$ 14.29 - $ 14.29
$ 14.29

Foster BL3003, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL3003 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 17.89
$ 17.89 - $ 17.89
$ 17.89
$ 14.29
$ 14.29 - $ 14.29
$ 14.29
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 %
$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99

Foster 3003, 1/4" Industrial Coupler x 1/4" Female NPT, 3 Series, 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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$ 14.99
$ 14.99 - $ 14.99
$ 14.99
$ 11.99
$ 11.99 - $ 11.99
$ 11.99
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 %
$ 23.19
$ 23.19 - $ 23.19
$ 23.19
$ 18.59
$ 18.59 - $ 18.59
$ 18.59

Foster 2803W, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Water, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803W is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 23.19
$ 23.19 - $ 23.19
$ 23.19
$ 18.59
$ 18.59 - $ 18.59
$ 18.59
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 %
$ 59.59
$ 59.59 - $ 59.59
$ 59.59
$ 47.69
$ 47.69 - $ 47.69
$ 47.69

Foster 2803S/S, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, 303 Stainless

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803S/S is a 303 Stainless 1/4" industrial coupler from the Foster 3 Serie...

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$ 59.59
$ 59.59 - $ 59.59
$ 59.59
$ 47.69
$ 47.69 - $ 47.69
$ 47.69
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 %
$ 23.59
$ 23.59 - $ 23.59
$ 23.59
$ 18.89
$ 18.89 - $ 18.89
$ 18.89

Foster 2803S, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Steam/EPDM, Brass/SS

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803S is a Brass/SS 1/4" industrial coupler from the Foster 3 Series — the...

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$ 23.59
$ 23.59 - $ 23.59
$ 23.59
$ 18.89
$ 18.89 - $ 18.89
$ 18.89
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 %
$ 22.19
$ 22.19 - $ 22.19
$ 22.19
$ 17.79
$ 17.79 - $ 17.79
$ 17.79

Foster 2803H, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Heat/Viton, Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803H is a Steel 1/4" industrial coupler from the Foster 3 Series — the mo...

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$ 22.19
$ 22.19 - $ 22.19
$ 22.19
$ 17.79
$ 17.79 - $ 17.79
$ 17.79
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 %
$ 19.49
$ 19.49 - $ 19.49
$ 19.49
$ 15.59
$ 15.59 - $ 15.59
$ 15.59

Foster BL2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Ball Lock, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster BL2803 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series —...

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$ 19.49
$ 19.49 - $ 19.49
$ 19.49
$ 15.59
$ 15.59 - $ 15.59
$ 15.59
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 %
$ 19.19
$ 19.19 - $ 19.19
$ 19.19
$ 15.29
$ 15.29 - $ 15.29
$ 15.29

Foster 2803, 1/4" Industrial Coupler x 1/8" Female NPT, 3 Series, Brass/Steel

Reliable, leak-free 1/4" connections for air and fluid lines. The Foster 2803 is a Brass/Steel 1/4" industrial coupler from the Foster 3 Series — t...

View full details
$ 19.19
$ 19.19 - $ 19.19
$ 19.19
$ 15.29
$ 15.29 - $ 15.29
$ 15.29
Save 20% Save %

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