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Small black forged steel square head pipe plug 1/4 inch NPT

Anvil

Anvil 1/4" forged steel square head plug 361300403

SKU CH-V4RH-CYYX9

A 1/4" forged steel square head plug rated for 300 psi at 150°F with a -20°F to 350°F operating range

  • Forged steel withstands 300 psi at 150 °F
  • Square head allows easy installation with a wrench
  • Male NPT threads seal pipe ends reliably
  • Operates from -20 °F to 350 °F for wide temperature range
  • Black finish protects against corrosion in plumbing systems

1/4" Forged Steel Square Head Plug

The Anvil 361300403 is a 1/4 inch nominal pipe size plug made from forged steel with a black finish. It features a male NPT thread and a solid square head for installation with a wrench. Rated for Class 150 service, it suits general-purpose piping systems carrying water, oil, gas or steam.

Suits low-pressure lines up to 300 psi

This plug fits standard NPT ports in plumbing, hydraulic or pneumatic circuits operating between -20 and 350 degrees Fahrenheit. It is not for systems exceeding the Class 150 pressure rating or for applications requiring a pre-applied thread sealant. Buyers needing a different thread type or a hollow plug should look elsewhere.

300 psi maximum at 150 degrees F

The decisive specification is the 300 psi maximum operating pressure at 150 degrees Fahrenheit. This limit defines whether the plug can handle the intended service conditions. Verify your system pressure and temperature against this rating before purchase.

Highlights

  • Forged steel withstands 300 psi at 150 °F
  • Square head allows easy installation with a wrench
  • Male NPT threads seal pipe ends reliably
  • Operates from -20 °F to 350 °F for wide temperature range
  • Black finish protects against corrosion in plumbing systems

Specifications

BrandANVIL

Questions about this item

What thread type must my pipe have for this 1/4" plug to seal?

The plug uses a male NPT thread, so the mating pipe or fitting needs a female NPT thread of the same 1/4" nominal size.

Will the 300 psi rating hold if I run it on a legacy system that only sees 150 psi?

Yes, the plug is rated for 300 psi at 150 °F, so a system operating at 150 psi is well within its pressure limit.

How can I confirm the plug is seated correctly after installation?

Tighten the square head with a wrench until the joint feels solid and no leaks appear when the system is pressurised up to its working pressure.

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