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Black reducing coupling, three-inch to one-inch FNPT threads

Legend Valve

Legend Valve 350-556 3" x 1" Black Reducing Coupling FNPT x FNPT

SKU CH-NF3P-3N9VJ

Connects 3-inch and 1-inch female NPT pipes with a black reducing coupling

  • Connects 3" and 1" pipes with FNPT threads
  • Black finish resists corrosion in plumbing systems
  • Reducing coupling enables size transition in one fitting
  • Legend Valve brand ensures reliable manufacturing quality
  • Meets California Proposition 65 chemical disclosure requirements

Product Identity

The Legend Valve 350-556 is a black reducing coupling that connects a three-inch female NPT thread to a one-inch female NPT thread. It is intended for plumbers and pipefitters joining black iron pipe in water, gas or oil lines where a straight size reduction is required. The fitting is supplied new and carries California Proposition 65 warnings for cancer and reproductive harm.

Who This Suits

Installers who need a direct female-to-female reduction between the two stated pipe sizes will find this coupling matches the thread specification. It is not for systems that require male threads, a different diameter combination, or a material other than black iron. Buyers needing a coupling for copper, PVC or stainless pipe should look at other product lines.

Deciding Specification

The thread interface is FNPT x FNPT in a 3" x 1" configuration, and this single detail determines whether the part fits the joint in question. Verify that both mating pipes carry the matching female NPT threads before purchasing.

Highlights

  • Connects 3" and 1" pipes with FNPT threads
  • Black finish resists corrosion in plumbing systems
  • Reducing coupling enables size transition in one fitting
  • Legend Valve brand ensures reliable manufacturing quality
  • Meets California Proposition 65 chemical disclosure requirements

Specifications

BrandLEGEND VALVE

Questions about this item

Will the 350-556 reducing coupling thread onto my existing 3-inch FNPT pipe and 1-inch FNPT fitting without adapters?

Yes, the coupling has FNPT threads on both ends — one sized for 3-inch pipe and the other for 1-inch pipe — so it connects directly to matching FNPT threads.

How can I verify the 350-556 coupling is sealed properly after installation?

Pressurise the system and check the joint for leaks; a correctly threaded and sealed FNPT connection should hold pressure without weeping at either the 3-inch or 1-inch end.

Does the 350-556 box include thread sealant or tape, or must I buy them separately?

The package contains only the black reducing coupling; pipe-thread sealant or tape is not included and must be purchased separately.

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