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Black 4 inch merchant coupling with NPT threads

Legend Valve

Legend Valve 350-712 4 inch Black Merchant Coupling

SKU CH-N1CX-N8YGY

A 4-inch black merchant coupling with NPT threads for joining pipe sections

  • 4 inch NPT connection fits standard piping
  • Black finish resists corrosion in plumbing systems
  • Merchant coupling design joins two pipe ends
  • Legend Valve brand trusted for plumbing components
  • New condition ensures reliable leak-free installation

4" Black Merchant Coupling

This 4-inch black merchant coupling connects two sections of NPT-threaded pipe in plumbing systems. The Legend Valve 350-712 model provides a straight mechanical joint for fluid conveyance. It is intended for installers and maintenance personnel assembling or repairing threaded pipe runs.

Threaded pipe connection

The coupling mates with male NPT threads on both ends, requiring compatible pipe nipples or fittings to complete a joint. Proper thread sealant or tape is needed to ensure a leak-free seal during assembly. No specialised tools beyond standard pipe wrenches are required for installation.

Suits NPT plumbing repairs

This fitting suits plumbers and contractors joining black iron or steel pipe in residential or commercial water, gas, or oil lines. It does not suit applications requiring push-fit, compression, or flanged connections. Buyers needing a reducing coupling, a different thread standard, or a non-metallic fitting should look at something else.

Highlights

  • 4 inch NPT connection fits standard piping
  • Black finish resists corrosion in plumbing systems
  • Merchant coupling design joins two pipe ends
  • Legend Valve brand trusted for plumbing components
  • New condition ensures reliable leak-free installation

Specifications

BrandLEGEND VALVE

Questions about this item

What is the first limit that shows up under sustained use?

The coupling is rated to Proposition 65 standards, so the first limit is the chemical exposure warning for cancer and reproductive harm.

How much noise, heat or power does it produce when running all day?

It is a passive 4-inch black merchant coupling with NPT threads, so it generates no noise, heat or power during operation.

What else must I already own for this coupling to work?

You need matching 4-inch NPT threaded pipe or fittings to connect the coupling into your plumbing system.

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