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Foster FST Series Couplers (Straight-Thru)

Foster FST Series full-flow straight-through hydraulic couplers and plugs — no valve in either half, so the inside diameter matches the nominal pipe for maximum flow. Standard Industrial Interchange with manual sleeve connection, body sizes 1/8" to 1-1/2". Brass, steel, and 303 stainless; ball-lock option available. Note: lines do not self-seal on disconnect.

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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 %
$ 226.00
$ 226.00 - $ 226.00
$ 226.00
$ 180.00
$ 180.00 - $ 180.00
$ 180.00

Foster 75FP, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FP is a steel 3/4" straight-thru plug i...

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$ 226.00
$ 226.00 - $ 226.00
$ 226.00
$ 180.00
$ 180.00 - $ 180.00
$ 180.00
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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 %
$ 281.00
$ 281.00 - $ 281.00
$ 281.00
$ 226.00
$ 226.00 - $ 226.00
$ 226.00

Foster 75FPB, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FPB is a brass 3/4" straight-thru plug ...

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$ 281.00
$ 281.00 - $ 281.00
$ 281.00
$ 226.00
$ 226.00 - $ 226.00
$ 226.00
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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 %
$ 903.00
$ 903.00 - $ 903.00
$ 903.00
$ 721.00
$ 721.00 - $ 721.00
$ 721.00

Foster 75FPS, 3/4" Straight-Thru Plug x 3/4" Female NPT, FST Series, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FPS is a 303 stainless 3/4" straight-th...

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$ 903.00
$ 903.00 - $ 903.00
$ 903.00
$ 721.00
$ 721.00 - $ 721.00
$ 721.00
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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 %
$ 653.00
$ 653.00 - $ 653.00
$ 653.00
$ 523.00
$ 523.00 - $ 523.00
$ 523.00

Foster 75FS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FS is a brass 3/4" straight-thru couple...

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$ 653.00
$ 653.00 - $ 653.00
$ 653.00
$ 523.00
$ 523.00 - $ 523.00
$ 523.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 741.00
$ 741.00 - $ 741.00
$ 741.00
$ 593.00
$ 593.00 - $ 593.00
$ 593.00

Foster 75FS-101, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Viton Seal, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FS-101 is a brass 3/4" straight-thru co...

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$ 741.00
$ 741.00 - $ 741.00
$ 741.00
$ 593.00
$ 593.00 - $ 593.00
$ 593.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 728.00
$ 728.00 - $ 728.00
$ 728.00
$ 584.00
$ 584.00 - $ 584.00
$ 584.00

Foster 75FS-103, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, EPDM Seal, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FS-103 is a brass 3/4" straight-thru co...

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$ 728.00
$ 728.00 - $ 728.00
$ 728.00
$ 584.00
$ 584.00 - $ 584.00
$ 584.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 758.00
$ 758.00 - $ 758.00
$ 758.00
$ 607.00
$ 607.00 - $ 607.00
$ 607.00

Foster 75FS-104, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Silicone Seal, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FS-104 is a brass 3/4" straight-thru co...

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$ 758.00
$ 758.00 - $ 758.00
$ 758.00
$ 607.00
$ 607.00 - $ 607.00
$ 607.00
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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 %
$ 2,146.00
$ 2,146.00 - $ 2,146.00
$ 2,146.00
$ 1,717.00
$ 1,717.00 - $ 1,717.00
$ 1,717.00

Foster 75FSS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FSS is a 303 stainless 3/4" straight-th...

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$ 2,146.00
$ 2,146.00 - $ 2,146.00
$ 2,146.00
$ 1,717.00
$ 1,717.00 - $ 1,717.00
$ 1,717.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 2,214.00
$ 2,214.00 - $ 2,214.00
$ 2,214.00
$ 1,770.00
$ 1,770.00 - $ 1,770.00
$ 1,770.00

Foster 75FSS-101, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Viton Seal, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FSS-101 is a 303 stainless 3/4" straigh...

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$ 2,214.00
$ 2,214.00 - $ 2,214.00
$ 2,214.00
$ 1,770.00
$ 1,770.00 - $ 1,770.00
$ 1,770.00
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 %
$ 2,247.00
$ 2,247.00 - $ 2,247.00
$ 2,247.00
$ 1,798.00
$ 1,798.00 - $ 1,798.00
$ 1,798.00

Foster 75FSS-103, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, EPDM Seal, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75FSS-103 is a 303 stainless 3/4" straigh...

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$ 2,247.00
$ 2,247.00 - $ 2,247.00
$ 2,247.00
$ 1,798.00
$ 1,798.00 - $ 1,798.00
$ 1,798.00
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 %
$ 319.00
$ 319.00 - $ 319.00
$ 319.00
$ 255.00
$ 255.00 - $ 255.00
$ 255.00

Foster 75HPB, 3/4" Straight-Thru Plug x 3/4" Hose ID, FST Series, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster 75HPB is a brass 3/4" straight-thru plug ...

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$ 319.00
$ 319.00 - $ 319.00
$ 319.00
$ 255.00
$ 255.00 - $ 255.00
$ 255.00
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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 %
$ 1,189.00
$ 1,189.00 - $ 1,189.00
$ 1,189.00
$ 950.00
$ 950.00 - $ 950.00
$ 950.00

Foster BL100FS, 1" Straight-Thru Coupler x 1" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL100FS is a brass 1" straight-thru coupl...

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$ 1,189.00
$ 1,189.00 - $ 1,189.00
$ 1,189.00
$ 950.00
$ 950.00 - $ 950.00
$ 950.00
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 %
$ 3,463.00
$ 3,463.00 - $ 3,463.00
$ 3,463.00
$ 2,770.00
$ 2,770.00 - $ 2,770.00
$ 2,770.00

Foster BL100FSS, 1" Straight-Thru Coupler x 1" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL100FSS is a 303 stainless 1" straight-t...

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$ 3,463.00
$ 3,463.00 - $ 3,463.00
$ 3,463.00
$ 2,770.00
$ 2,770.00 - $ 2,770.00
$ 2,770.00
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 %
$ 3,184.00
$ 3,184.00 - $ 3,184.00
$ 3,184.00
$ 2,548.00
$ 2,548.00 - $ 2,548.00
$ 2,548.00

Foster BL125FS, 1-1/4" Straight-Thru Coupler x 1-1/4" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL125FS is a brass 1-1/4" straight-thru c...

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$ 3,184.00
$ 3,184.00 - $ 3,184.00
$ 3,184.00
$ 2,548.00
$ 2,548.00 - $ 2,548.00
$ 2,548.00
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 %
$ 340.00
$ 340.00 - $ 340.00
$ 340.00
$ 272.00
$ 272.00 - $ 272.00
$ 272.00

Foster BL12FS, 1/8" Straight-Thru Coupler x 1/8" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL12FS is a brass 1/8" straight-thru coup...

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$ 340.00
$ 340.00 - $ 340.00
$ 340.00
$ 272.00
$ 272.00 - $ 272.00
$ 272.00
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 %
$ 877.00
$ 877.00 - $ 877.00
$ 877.00
$ 701.00
$ 701.00 - $ 701.00
$ 701.00

Foster BL12FSS, 1/8" Straight-Thru Coupler x 1/8" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL12FSS is a 303 stainless 1/8" straight-...

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$ 877.00
$ 877.00 - $ 877.00
$ 877.00
$ 701.00
$ 701.00 - $ 701.00
$ 701.00
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 %
$ 5,526.00
$ 5,526.00 - $ 5,526.00
$ 5,526.00
$ 4,420.00
$ 4,420.00 - $ 4,420.00
$ 4,420.00

Foster BL150FS, 1-1/2" Straight-Thru Coupler x 1-1/2" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL150FS is a brass 1-1/2" straight-thru c...

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$ 5,526.00
$ 5,526.00 - $ 5,526.00
$ 5,526.00
$ 4,420.00
$ 4,420.00 - $ 4,420.00
$ 4,420.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 378.00
$ 378.00 - $ 378.00
$ 378.00
$ 303.00
$ 303.00 - $ 303.00
$ 303.00

Foster BL25FS, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL25FS is a brass 1/4" straight-thru coup...

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$ 378.00
$ 378.00 - $ 378.00
$ 378.00
$ 303.00
$ 303.00 - $ 303.00
$ 303.00
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 %
$ 1,348.00
$ 1,348.00 - $ 1,348.00
$ 1,348.00
$ 1,079.00
$ 1,079.00 - $ 1,079.00
$ 1,079.00

Foster BL25FSS, 1/4" Straight-Thru Coupler x 1/4" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL25FSS is a 303 stainless 1/4" straight-...

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$ 1,348.00
$ 1,348.00 - $ 1,348.00
$ 1,348.00
$ 1,079.00
$ 1,079.00 - $ 1,079.00
$ 1,079.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 439.00
$ 439.00 - $ 439.00
$ 439.00
$ 351.00
$ 351.00 - $ 351.00
$ 351.00

Foster BL38FS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL38FS is a brass 3/8" straight-thru coup...

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$ 439.00
$ 439.00 - $ 439.00
$ 439.00
$ 351.00
$ 351.00 - $ 351.00
$ 351.00
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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 %
$ 1,453.00
$ 1,453.00 - $ 1,453.00
$ 1,453.00
$ 1,161.00
$ 1,161.00 - $ 1,161.00
$ 1,161.00

Foster BL38FSS, 3/8" Straight-Thru Coupler x 3/8" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL38FSS is a 303 stainless 3/8" straight-...

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$ 1,453.00
$ 1,453.00 - $ 1,453.00
$ 1,453.00
$ 1,161.00
$ 1,161.00 - $ 1,161.00
$ 1,161.00
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 %
$ 567.00
$ 567.00 - $ 567.00
$ 567.00
$ 453.00
$ 453.00 - $ 453.00
$ 453.00

Foster BL50FS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL50FS is a brass 1/2" straight-thru coup...

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$ 567.00
$ 567.00 - $ 567.00
$ 567.00
$ 453.00
$ 453.00 - $ 453.00
$ 453.00
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Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 1,642.00
$ 1,642.00 - $ 1,642.00
$ 1,642.00
$ 1,313.00
$ 1,313.00 - $ 1,313.00
$ 1,313.00

Foster BL50FSS, 1/2" Straight-Thru Coupler x 1/2" Female NPT, FST Series, Ball Lock, 303 Stainless Steel

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL50FSS is a 303 stainless 1/2" straight-...

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$ 1,642.00
$ 1,642.00 - $ 1,642.00
$ 1,642.00
$ 1,313.00
$ 1,313.00 - $ 1,313.00
$ 1,313.00
Save 20% Save %
Foster BLH1B, 1/8" ISO-B Hydraulic Coupler x 1/8" Female NPT, ISO-B Series, Ball Lock, Brass
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$ 860.00
$ 860.00 - $ 860.00
$ 860.00
$ 688.00
$ 688.00 - $ 688.00
$ 688.00

Foster BL75FS, 3/4" Straight-Thru Coupler x 3/4" Female NPT, FST Series, Ball Lock, Brass

Maximum flow with no restriction, for air and fluid lines where shut-off is handled elsewhere. The Foster BL75FS is a brass 3/4" straight-thru coup...

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$ 860.00
$ 860.00 - $ 860.00
$ 860.00
$ 688.00
$ 688.00 - $ 688.00
$ 688.00
Save 20% Save %

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