3/8 inch Brass Square Head Plug

3/8 inch Brass Square Head Plug – NPT Threaded for General Service Applications

The 3/8 Inch Brass Square Head Plug is a solid male-threaded fitting used to seal unused or terminated female-threaded openings in pressure and non-pressure piping systems. Constructed from corrosion-resistant, lead-free brass, this plug is suitable for use in potable water, air, oil, and low-pressure steam systems as permitted by applicable code.

Construction and Functional Characteristics

This plug features a square head for easy wrench access and installation in confined spaces. Machined NPT threads ensure a tight fit, minimizing the risk of leakage in properly assembled piping networks. Its forged brass body maintains mechanical strength under moderate pressure and temperature conditions.

• ✅ Material: Lead-Free Brass (complies with NSF 61/372)
• ✅ Thread Profile: Male NPT, conforming to ANSI B1.20.1 for tapered pipe threads
• ✅ Head Style: Square head for torque application via open-end or adjustable wrench
• ✅ Service Use: Suitable for potable water, air, gas, and general utility piping (verify local code for approval)

Technical Specifications

• Size: 3/8 Inch NPT (Nominal)
• Material: Forged Lead-Free Brass (typically CW510L or equivalent)
• Working Pressure: Up to 200 PSI (varies by system design and media)
• Temperature Range: Typically rated -20°F to 400°F, depending on media and sealants used

Installation Guidelines

Apply PTFE tape or approved thread sealant to the male threads prior to installation. Engage threads by hand and complete installation with a wrench, applying torque appropriate to thread size and system type. Avoid over-tightening to prevent damage to mating threads or deformation of pipe fittings.

Common Applications

Frequently used in residential, commercial, and industrial plumbing systems to cap off pipe runs, test ports, unused valve outlets, or branch lines. Also suitable for hydronic heating systems, air compressor assemblies, and mechanical piping installations requiring reliable pipe termination.

Material Note

Brass fittings offer strong resistance to dezincification and stress cracking in water systems. The use of lead-free brass supports compliance with federal and state potable water regulations, especially in public buildings and food service environments.

The 3/8 inch Brass Square Head Plug provides a durable, corrosion-resistant seal for terminated ports in threaded piping systems. Its compact, code-compliant design supports a wide range of mechanical, water, and gas distribution applications.