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Small stainless steel hex socket plug with male threads

Zoro Select

Zoro Select 3/8 in. MNPT 304 Stainless Steel Hex Socket Plug Class 150

SKU CH-KBAP-XP123

A 304 stainless steel hex socket plug with 3/8-inch MNPT threads, Class 150 rating for 300 psi and -60 to 450 °F service

  • 304 stainless steel resists corrosion in harsh environments
  • Class 150 rating handles up to 300 psi working pressure
  • Operates from -60 to 450 °F for extreme temperatures
  • Internal 5/16 in. hex drive allows Allen-key installation
  • Meets ASTM A351 standard for material quality

3/8-inch MNPT hex socket plug

This 304 stainless steel hex socket plug closes the end of a 3/8-inch male national pipe thread port. The internal 5/16-inch hex recess accepts a standard Allen key for installation and removal. It conforms to ASTM A351 standards and carries a Class 150 pressure rating.

Replaces open ports and temporary caps

The fitting upgrades from makeshift seals or lower-grade plugs when a permanent, corrosion-resistant closure is required. The jump is worth it for systems operating up to 300 psi and between -60 and 450 degrees Fahrenheit where 304 stainless steel compatibility is specified.

Simple Allen-key installation

Thread sealant must be applied per standard piping practice because none is pre-applied. The 12.7 mm overall length fits shallow ports, but the small hex size demands a well-fitting wrench to avoid rounding the recess during tightening.

Highlights

  • 304 stainless steel resists corrosion in harsh environments
  • Class 150 rating handles up to 300 psi working pressure
  • Operates from -60 to 450 °F for extreme temperatures
  • Internal 5/16 in. hex drive allows Allen-key installation
  • Meets ASTM A351 standard for material quality

Specifications

BrandZORO SELECT

Questions about this item

What hex wrench size fits the 5/16 inch internal recess on this 3/8 inch MNPT plug?

Use a 5/16 inch Allen key or hex wrench to engage the internal hexagonal recess for tightening or removal.

Should I apply thread sealant before installing the 3/8 inch MNPT stainless plug?

Yes, the fitting has no pre-applied sealant; apply appropriate thread sealant to the male national pipe threads per standard piping practice.

Will the 304 stainless steel plug need replacement due to corrosion within its -60 to 450 °F rating?

304 stainless steel resists corrosion across the rated temperature range; replacement is only needed if mechanical damage or thread wear occurs.

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