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Round malleable iron pipe cap with female NPT threads

Value Brand

Value Brand 3/8" FNPT Malleable Iron Cap 150 Class

SKU CH-NDHD-C4YFC

Malleable iron cap with 3/8 inch female NPT threads, rated Class 150 for temperatures from -20 to 366 degrees Fahrenheit

  • Malleable iron construction resists cracking under pressure
  • Class 150 rating handles up to 150 psi service
  • Female NPT threads seal without separate sealant
  • Operates from -20 °F to 366 °F temperature range
  • California Proposition 65 warning for chemical exposure

3/8" FNPT Malleable Iron Cap 150 Class

This 3/8 inch female NPT cap is made from malleable iron and rated to Class 150. It is designed to close the end of a threaded pipe in plumbing or industrial piping systems. The fitting suits installers who need a durable, pressure-rated closure for water, air or compatible fluids. It is supplied new and ready for installation.

Check thread type and pressure rating

Verify that the existing pipe uses 3/8 inch NPT threads before ordering. The cap is rated for Class 150 service and an operating temperature range of -20 to 366 degrees F. Confirm that the system pressure and media are compatible with malleable iron and that no additional sealant is required unless your practice specifies it. The product carries a California Proposition 65 warning for chemicals known to cause cancer and reproductive harm.

Malleable iron construction and thread sealant note

The malleable iron body provides mechanical strength for threaded connections in demanding environments. No pre-applied thread sealant is included, so installers must apply their preferred sealant or tape during assembly. The female NPT threads allow direct engagement with male-threaded pipe or fittings. The cap contains no integrated seal or gasket, relying on proper thread engagement and sealant for a leak-free joint.

Highlights

  • Malleable iron construction resists cracking under pressure
  • Class 150 rating handles up to 150 psi service
  • Female NPT threads seal without separate sealant
  • Operates from -20 °F to 366 °F temperature range
  • California Proposition 65 warning for chemical exposure

Specifications

BrandZORO SELECT

Questions about this item

What comes with the 3/8" malleable iron cap?

The package contains the Class 150 female NPT cap only. Thread sealant and a separate seal are not included, so have pipe tape or compound ready for installation.

When should I choose the Class 150 version of this 3/8" cap?

Select this cap for piping systems rated to 150 psi at ambient temperature. It handles service from -20 °F to 366 °F, making it suitable for standard water, air and steam lines within that pressure class.

What does the 150 Class rating mean once the cap is threaded on?

It certifies the fitting for 150 psi working pressure at room temperature, with a maximum service temperature of 366 °F. Pressure capacity decreases as temperature rises, so verify your system stays within the rated limits.

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