We take cryptocurrency — so the coins you hold can buy real hardware.Pay in crypto, spend it on real hardware. Free insured shipping worldwide over $399. Plain, unbranded boxes, sent from Germany.Free insured shipping over $399. Your rate is locked for 30 minutes once checkout opens.Rate locked 30 minutes. Every item sealed, serial-checked and covered by a 24-month warranty.Sealed, 24-month warranty.

Saved items Sign in
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.

How it compares

Measured against everything we stock in Hose Fittings, Adapters & Clamps, at today’s prices. Recalculated every night.

Price $24.99
Pricier than about 61% of the 2,955 comparable items (median $17.99).

Specifications

Product
Brand nameLEGEND 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.

More in Hose Fittings, Adapters & Clamps

Similar items