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Black three-inch union coupling with threaded ends

Legend Valve

Legend Valve 350-450 3 inch Black Union coupling

SKU CH-8JGV-5EYYJ

Three-inch black union coupling with FNPT threads connects pipe sections

  • 3-inch black union connects piping systems reliably
  • 350 to 450 model range suits specified pressure needs
  • FNPT x FNPT threads enable direct pipe attachment
  • California Proposition 65 listed for cancer risk awareness
  • California Proposition 65 listed for reproductive harm awareness

3 inch Black Union coupling

The Legend Valve 350-450 is a 3 inch black union coupling designed for plumbing installations. It connects two female NPT threaded pipes using a union nut that allows quick disassembly. The fitting suits residential and commercial water or gas lines where a removable joint is required. Buyers who need a flanged, compression or push-fit connection cannot use this coupling.

Check your setup before ordering

Verify that both pipe ends have clean female NPT threads matching the 3 inch nominal size. Confirm the system pressure stays within the coupling's rated working range. Ensure the black finish material is compatible with the fluid being conveyed and local code requirements. Installers without thread sealant or a suitable wrench for the union nut should obtain those before starting the job.

Replaces worn or leak-prone unions

This coupling replaces an existing 3 inch black FNPT union that is corroded, cracked or no longer seals. The upgrade is worth it when the old union leaks under pressure or during disassembly for maintenance. It also serves as a direct spare for scheduled pipework revisions where a removable joint simplifies future service. Do not use it to change pipe diameter or thread standard.

Highlights

  • 3-inch black union connects piping systems reliably
  • 350 to 450 model range suits specified pressure needs
  • FNPT x FNPT threads enable direct pipe attachment
  • California Proposition 65 listed for cancer risk awareness
  • California Proposition 65 listed for reproductive harm awareness

Specifications

BrandLEGEND VALVE

Questions about this item

Does the 3 inch black union coupling come with any gaskets or sealant in the box, or do I need to buy them separately?

The package contains only the union coupling itself; thread sealant or gaskets must be purchased separately.

How do I decide between the 350 and 450 pressure ratings shown in the model number?

Choose the rating that matches or exceeds your system's maximum working pressure; 350 suits lower-pressure lines while 450 covers higher-pressure applications.

What does the 3 inch FNPT x FNPT specification mean when I install this union in a real plumbing line?

Both ends have female National Pipe Threads sized for 3 inch nominal pipe, so you thread male‑threaded pipe or nipples directly into each side.

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