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Square head stainless steel pipe plug 1/8 inch MNPT threads silver finish

Zoro Select

Zoro Select Square Head Plug 1/8 in MNPT 304 Stainless Steel

SKU CH-FZ7M-YSCH5

A 1/8 in MNPT square-head plug in 304 stainless steel rated for 300 psi and 150 psi steam up to 350 °F

  • 1/8 in MNPT fits standard pipe threads
  • 304 stainless steel resists corrosion in harsh environments
  • Class 150 rating handles 300 psi operating pressure
  • Solid hex drive allows secure installation with wrench
  • Temperature range -20 to 350 °F suits steam and fluid lines

Square Head Plug 1/8 in MNPT

This Zoro Select plug is a solid stainless steel fitting designed to close a 1/8 inch male NPT threaded port. It suits maintenance engineers and pipefitters who need a reliable seal in general industrial piping systems. The Class 150 rating and Schedule 40 compatibility define its intended service range. It is not for buyers who need a plug with pre-applied sealant or an integrated gasket.

Pressure and Temperature Limits

The fitting carries a maximum operating pressure of 300 psi and a maximum steam pressure of 150 psi. Its 304 stainless steel construction handles temperatures from -20 degrees to 350 degrees F. These ratings set the practical boundary for water, oil, air and saturated steam lines. It is not for systems that exceed these pressure or temperature values or that require a higher pressure class.

Installation and Common Issues

A hex drive allows tightening with a standard wrench or socket for straightforward installation. Because no thread sealant is pre-applied, the installer must supply PTFE tape or pipe dope matched to the media. The most common fault is leakage caused by insufficient sealant or over-tightening that distorts the threads. It is not for applications where a tool-free or hand-tight seal is required.

Highlights

  • 1/8 in MNPT fits standard pipe threads
  • 304 stainless steel resists corrosion in harsh environments
  • Class 150 rating handles 300 psi operating pressure
  • Solid hex drive allows secure installation with wrench
  • Temperature range -20 to 350 °F suits steam and fluid lines

Specifications

BrandZORO SELECT

Questions about this item

Is the 1/8 in MNPT size the right fit for my Schedule 40 piping?

Yes, this plug matches 1/8 in nominal pipe size and Schedule 40, so it threads directly into that piping class.

What does the 300 psi rating mean when the plug is installed?

It indicates a maximum operating pressure of 300 psi at temperatures from -20 to 350 degrees F, with a lower 150 psi limit for steam service.

How does the MNPT thread standard affect sealing in practice?

The 1/8-27 MNPT taper threads create a mechanical seal when tightened, and no pre-applied sealant or gasket is included.

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