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Four-inch bronze square-head threaded plug with no-lead finish

Legend Valve

Legend Valve 310-191NL 4" Bronze Square Head Plug No Lead

SKU CH-20ZS-XW01B

A 4-inch threaded bronze square-head plug with no-lead construction for plumbing systems

  • No-lead bronze meets California Proposition 65 compliance
  • 4-inch male NPT threads fit standard pipe sizes
  • Square head design allows secure wrench tightening
  • Cast bronze construction resists corrosion in water systems
  • Legend Valve 310-191NL model ensures consistent quality

4" Bronze Square Head Plug

This 4-inch threaded plug is made from no-lead cast bronze and carries a square head for wrench engagement. It is intended for plumbing systems that require a lead-free connection on male NPT threads.

Installers needing lead-free bronze fittings

The plug suits potable-water and hydronic applications where no-lead material is mandated. It will not fit systems using compression, push-fit or flanged connections, and it is not sized for smaller or larger pipe diameters.

Threaded installation with a square wrench

The square head allows tightening with a standard adjustable or fixed wrench. Common issues include cross-threading when the male threads are damaged and leaks if thread sealant is omitted or applied incorrectly.

Highlights

  • No-lead bronze meets California Proposition 65 compliance
  • 4-inch male NPT threads fit standard pipe sizes
  • Square head design allows secure wrench tightening
  • Cast bronze construction resists corrosion in water systems
  • Legend Valve 310-191NL model ensures consistent quality

Specifications

BrandLEGEND VALVE

Questions about this item

What size threaded opening do I need for the 4" MNPT connection on this plug?

This plug uses a 4" male national pipe thread so the matching opening must be a 4" female NPT fitting.

Will the no-lead bronze material cause galvanic issues if I thread it into an older brass fitting?

The no-lead cast bronze body is compatible with standard brass pipe threads and does not create galvanic corrosion in typical water systems.

How can I confirm the square head is properly seated after installation?

The square head should sit flush against the fitting face with no visible thread gaps and the joint should hold pressure without weeping.

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