Parker 66HD-4-4 Compression Tube Connector 1/4 in Brass

Product Description

The PARKER 66HD-4-4 is a brass compression tube connector designed to join tubing to female NPT threaded ports in fluid and gas distribution systems. It features a 1/4-inch thread size with compression-to-FNPT end connections, making it suitable for creating secure, leak-resistant joints without soldering or welding. Rated to a maximum working pressure of 2100 psi, this connector is built for demanding applications where pressure integrity is critical. Licensed plumbers, HVAC technicians, and instrumentation specialists routinely specify this fitting type in control line and refrigerant-adjacent tubing assemblies.

This connector is used in residential and commercial plumbing, HVAC control tubing, pneumatic instrument lines, and refrigeration service piping where a compression-style connection to a female NPT port is required. The all-brass construction resists corrosion and holds up across a wide temperature range, from -65 degrees F to 121 degrees C (approximately 250 degrees F), making it adaptable to both low-temperature and moderate high-temperature service environments.

Key Features

• Compression x FNPT end connections for tool-friendly, no-solder installation
• Brass construction provides corrosion resistance in fluid and gas service
• 2100 psi maximum working pressure for high-pressure line applications
• 1/4-inch thread size fits standard FPT ported valves, manifolds, and equipment
• Wide service temperature range: -65 degrees F to approximately 250 degrees F

Compatibility

Designed as an OEM-style replacement or new-installation fitting for systems requiring a 1/4-inch compression-to-FNPT brass connector in fluid, gas, or pneumatic tubing circuits.

Installation Notes

This fitting is installed by licensed plumbers or HVAC technicians following applicable IPC and mechanical code requirements. Before installation, shut off all pressure to the line being serviced and verify the tubing is properly cut, deburred, and squared. Hand-tighten the compression nut onto the fitting body, then snug with a wrench — do not over-torque, as brass fittings are susceptible to thread damage. Verify for leaks at working pressure before returning the system to service.