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Stainless steel reducing coupling with threaded ends

Legend Valve

Legend Valve 404-403 4" x 2-1/2" SS304 Reducing Coupling equipment

SKU CH-PTXP-BBZP0

A 304 stainless-steel reducing coupling with FNPT threads connects 4-inch and 2-1/2-inch pipe sizes

  • 304 stainless steel resists corrosion in harsh environments
  • Reducing design connects 4 inch to 2-1/2 inch FNPT threads
  • Legend Valve brand backs industrial-grade reliability
  • New condition ensures full factory performance from day one
  • Prop 65 notice alerts installers to regulated chemical content

4" x 2-1/2" SS304 Reducing Coupling

The Legend Valve 404-403 is a 304 stainless steel reducing coupling designed to join a 4 inch female NPT thread to a 2-1/2 inch female NPT thread. It suits industrial plumbing systems that require a corrosion-resistant transition between different pipe sizes.

Installers needing a direct FNPT reduction

This coupling fits technicians who must connect two female-threaded pipes of unequal diameter in water, oil or gas lines where 304 stainless steel is specified. Buyers who need a coupling for male-threaded pipes, a different alloy, or a straight equal-size joint should look at other fittings.

Verify thread standards and chemical compatibility

Confirm that both pipe ends are cut to female NPT dimensions so the coupling engages correctly. Check that the process fluid is compatible with 304 stainless steel and review the Proposition 65 notice regarding listed chemicals before installation.

Highlights

  • 304 stainless steel resists corrosion in harsh environments
  • Reducing design connects 4 inch to 2-1/2 inch FNPT threads
  • Legend Valve brand backs industrial-grade reliability
  • New condition ensures full factory performance from day one
  • Prop 65 notice alerts installers to regulated chemical content

Specifications

BrandLEGEND VALVE

Questions about this item

What size female NPT threads must the existing pipework have to accept this 4" x 2-1/2" reducing coupling?

The coupling connects a 4 inch female NPT thread on one side to a 2-1/2 inch female NPT thread on the other, so both mating pipes need matching male NPT ends.

Will the 304 stainless steel body resist corrosion when joined to older galvanised or black iron pipe in the same system?

304 stainless steel offers good general corrosion resistance, but direct contact with dissimilar metals such as galvanised or black iron can create galvanic cells; dielectric unions or appropriate thread sealant are recommended to minimise accelerated corrosion.

How can I verify the coupling is sealed correctly after threading it onto the pipe?

Pressurise the system to its working pressure and inspect both threaded joints for visible leaks; a properly sealed joint shows no moisture or pressure drop over the test period.

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