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Value Brand

Value Brand 1/4" x 1/8" FNPT Red Brass Reducing Coupling

SKU CH-RNJT-KTHX8

Red brass reducing coupling joins 1/4" to 1/8" FNPT threads, rated 125 psi from -20 to 400°F per ASTM B584 and ASME B16.15

  • TypeOther
  • Red brass construction resists corrosion for long service life
  • Class 125 rating supports up to 125 psi working pressure
  • FNPT threads create a tight seal without extra sealant
  • Operates from -20 to 400 degrees F for wide temperature range
  • Meets ASTM B584, ASME B16.15 and ANSI B1.20.1 standards

Red Brass Reducing Coupling

This Value Brand coupling joins a 1/4 inch female NPT thread to an 1/8 inch female NPT thread in plumbing and hydronic systems. The red brass construction meets ASTM B584 and ASME B16.15 standards for potable water and general piping use. It is a new component for installers who need a straight thread reduction in a single fitting.

125 psi Rating and Temperature Range

The fitting is rated for a maximum pressure of 125 psi across a temperature range of -20 to 400 degrees Fahrenheit. Red brass material resists dezincification and handles thermal cycling in hot water or steam lines. No moving parts or seals mean silent operation and no additional power draw in the system.

Class 125 FNPT Thread Compatibility

The coupling uses ANSI B1.20.1 tapered pipe threads on both ends for a secure seal with thread tape or compound. It fits Class 125 piping assemblies and frees up space compared to a bushing and nipple combination. Installers must verify thread compatibility and pressure requirements before assembly. California Proposition 65 warnings apply.

Highlights

  • Red brass construction resists corrosion for long service life
  • Class 125 rating supports up to 125 psi working pressure
  • FNPT threads create a tight seal without extra sealant
  • Operates from -20 to 400 degrees F for wide temperature range
  • Meets ASTM B584, ASME B16.15 and ANSI B1.20.1 standards

Specifications

BrandZORO SELECT
TypeOther

Questions about this item

How do I install the 1/4" x 1/8" FNPT reducing coupling without damaging the threads?

Apply PTFE tape or pipe dope to the male threads only, then hand-tighten before using two wrenches to finish; over-tightening the female ends is the common error that cracks the red brass body.

What maintenance will this Class 125 red brass coupling need over time?

Inspect the joint annually for green patina or weeping; re-apply thread sealant if a leak appears, and replace the fitting if dezincification makes the brass brittle.

Which limit appears first when the line runs near 125 psi at 400 °F?

The 125 psi pressure rating is reached before the 400 °F temperature ceiling, so pressure is the governing constraint under sustained high-load conditions.

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