Parker 398P-6-4 Compression Tube Shutoff Fitting

Product Description

The PARKER 398P-6-4 is a brass compression tube single end shutoff fitting configured for tube-to-pipe connections. It accepts a 1/4-18 NPTF threaded pipe end and uses a compression-style tube connection on the other end, providing a shutoff function in a single compact body. Rated for a maximum working pressure of 150 psi and a temperature range of 0 degrees F to 150 degrees F, this fitting is suited for fluid and low-pressure pneumatic lines found in HVAC, plumbing, and light industrial applications. Installation is handled by licensed plumbers or HVAC technicians working with copper or compatible tubing systems.

This fitting is used in residential and light commercial applications where a serviceable shutoff point is needed at a tube-to-pipe transition. Common install scenarios include supply line connections to equipment, branch takeoffs in refrigerant-free fluid systems, and maintenance isolation points. The NPTF thread standard ensures a pressure-tight mechanical seal without relying solely on sealant tape.

Key Features

• Single end shutoff function integrated into a tube-to-pipe compression fitting body
• 1/4-18 NPTF thread for a dry-seal, pressure-tight pipe connection
• Brass construction for corrosion resistance in wet and humid service environments
• Rated to 150 psi maximum working pressure
• Operating temperature range of 0 degrees F to 150 degrees F
• Compression tube end eliminates the need for soldering or flaring at the tube side

Compatibility

Designed as an OEM-style replacement or new-installation compression shutoff fitting for tube-to-pipe configurations using 1/4-18 NPTF threaded connections in plumbing, HVAC, and fluid-handling systems.

Installation Notes

Installation should be performed by a licensed plumber or qualified HVAC technician. Shut off and depressurize the supply line completely before disassembling any fitting or making new connections. NPTF threads are designed for dry-seal engagement, but consult applicable IPC or system specifications regarding the use of thread sealant. Do not overtighten the compression nut, as brass fittings are susceptible to thread damage and ferrule distortion under excessive torque.