Merit Brass K419-08 Pipe Locknut 1/2 in 304 Ss Threaded

Product Description

The MERIT BRASS K419-08 is a 1/2 inch pipe locknut manufactured from 304 stainless steel for use in threaded piping systems. Locknuts are used to secure fittings, bushings, or conduit connections at panel walls, enclosures, and bulkhead penetrations, holding the assembly firmly in place against vibration or movement. This unit features a female national pipe straight locknut (FNPSL) end connection and carries a 150 psi pressure rating. At 0.09 pounds, it is a lightweight but corrosion-resistant fastening component suited for plumbing, instrumentation, and light industrial piping applications. Installation is typically performed by licensed plumbers or pipefitters working on fluid or gas distribution systems.

This locknut is appropriate for residential and light commercial piping installations where a 1/2 inch threaded connection requires mechanical retention at a panel, tank wall, or enclosure. The 304 stainless steel construction makes it suitable for applications involving moisture, mild chemicals, or corrosive environments where carbon steel fittings would be prone to rust. It conforms to ISO standards, making it compatible with metric and internationally specified piping assemblies as well. The FNPSL thread form is designed for straight-thread engagement rather than tapered sealing, so proper gasket or o-ring sealing at the mating surface is standard practice.

Key Features

• 304 stainless steel construction for corrosion resistance in wet or mildly chemical environments
• 1/2 inch FNPSL (female national pipe straight locknut) end connection
• 150 psi pressure rating suitable for low- to medium-pressure piping systems
• Threaded connection type for straightforward hand-tool installation
• Meets ISO standards for compatibility with internationally specified piping assemblies
• Compact at 1-7/32 inches in length and 0.09 pounds

Compatibility

Designed as an OEM-style replacement or new-installation component for 1/2 inch threaded pipe systems requiring a straight-thread locknut with FNPSL connection in 304 stainless steel.

Installation Notes

This locknut is installed by licensed plumbers or pipefitters using standard pipe wrenches or open-end wrenches. Shut off and depressurize the piping system fully before removing or installing any threaded fittings. Because the FNPSL thread form does not provide a tapered pressure seal on its own, ensure that a suitable gasket or o-ring is in place at the mating face before torquing the locknut. Follow applicable IPC or facility-specific piping codes for assembly and pressure testing requirements.