Parker 66C-4-4 Compression Tube Connector Brass 300 Psi

Product Description

The PARKER 66C-4-4 is a brass compression tube connector designed to join 1/4-inch OD tubing to a female NPT port using a compression-to-FNPT end connection. Rated for up to 300 psi maximum working pressure, this connector handles a wide service temperature range from -65 degrees F to 250 degrees F, making it suitable for fuel, hydraulic, and instrumentation lines in both stationary and mobile equipment. The fitting meets SAE J-512 standards and is machined from brass for corrosion resistance in fluid-handling systems. Licensed HVAC technicians, plumbers, and fluid power mechanics typically install this type of connector in refrigeration, pneumatic, and low-pressure hydraulic circuits.

This connector is well suited for residential and commercial applications where a 1/4-inch OD tube must transition to a 1/4-18 NPTF female threaded port. Typical installations include instrument tubing runs, refrigeration oil lines, compressed air systems, and fuel supply circuits. Its compact form allows use in tight panel or equipment-cabinet spaces where a straight compression-to-pipe-thread transition is required.

Key Features

• Compression x FNPT end connections for a leak-resistant tube-to-pipe-thread transition
• 300 psi maximum working pressure rating
• Service temperature range: -65 degrees F to 250 degrees F
• Brass construction for corrosion resistance in fuel, air, and fluid service
• Meets SAE J-512 fitting standard
• 1/4-18 NPTF thread size for positive sealing engagement

Compatibility

Designed as an OEM-style compression fitting for use with 1/4-inch OD tubing and 1/4-18 NPTF female-threaded ports in fluid-handling, pneumatic, and refrigeration systems.

Installation Notes

A licensed plumber, HVAC technician, or fluid power mechanic should install this fitting in accordance with applicable system codes and the equipment manufacturer's guidelines. Shut off and depressurize the system completely before disassembly or installation. Hand-tighten the compression nut onto the tube before applying a final wrench turn to seat the ferrule; do not overtighten, as brass fittings can be damaged by excessive torque. Verify system pressure does not exceed the 300 psi rated maximum before returning the circuit to service.