Parker 66C-3-4 Compression Tube Connector Brass Fnpt

Product Description

The PARKER 66C-3-4 is a brass compression tube connector designed to join tubing to female NPT threaded ports in fluid and gas line assemblies. It features a compression fitting on one end and a female NPTF thread on the other, providing a secure, leak-resistant connection without the need for flaring. Rated to 400 psi maximum working pressure and capable of handling temperatures from -65 degrees F to 250 degrees F, this connector suits demanding service environments across HVAC, plumbing, and pneumatic applications. Plumbers, HVAC technicians, and pipefitters regularly use this fitting in both light commercial and residential installations.

The 66C-3-4 is suited for use in refrigeration lines, pneumatic controls, hydraulic systems, and general fluid handling where a compression-to-FNPT transition is required. Its 1/4-18 NPTF thread size is a standard dimension common across a wide range of valves, manifolds, and control components. The brass construction resists corrosion in wet or humid environments, making it a reliable choice for exposed or semi-exposed piping runs.

Key Features

• Compression x FNPT end connections allow tubing to thread into female NPT ports without flaring
• Rated to 400 psi maximum working pressure for use in pressurized fluid and gas lines
• Wide temperature range of -65 degrees F to 250 degrees F suits refrigeration and hot-fluid service
• 1/4-18 NPTF thread standard ensures a pressure-tight mechanical seal
• Brass construction provides corrosion resistance in wet and humid service conditions

Compatibility

Designed as an OEM-style replacement or new-installation fitting for systems requiring a 1/4-18 NPTF compression-to-female-NPT tube connector in brass construction.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or qualified pipefitter. Shut off and depressurize the line completely before removing or installing any compression fitting. Ensure the tubing end is cut cleanly and squarely and that the ferrule is seated properly before tightening the compression nut. Follow applicable codes including IFGC or IPC as appropriate for the service type.