Parker 66AB-4-4 Compression Tube Connector 1/4-18 Nptf

Product Description

The PARKER 66AB-4-4 is a brass compression tube connector designed to join a compression tube end to a female NPT (FNPT) port in fluid and pneumatic line assemblies. The fitting uses a 1/4-18 NPTF thread on the pipe side and a compression connection on the tube side, creating a reliable, leak-resistant seal without soldering or flaring. Rated to 400 psi maximum working pressure, it handles service temperatures from -65 degrees F to 250 degrees F. Manufactured from brass, the 66AB-4-4 meets DOT FMVSS571.106 and SAE J246 standards, making it suitable for brake, fuel, and hydraulic line applications that require certified fittings.

This connector is used in residential, commercial, and mobile equipment plumbing and pneumatic systems where a compression tube must terminate at a female NPT port. Typical installations include refrigeration and HVAC copper tubing connections, automotive and truck brake line assemblies, compressed air distribution lines, and hydraulic control circuits. The 1/4-18 thread size is a common size in light-duty fluid power and gas distribution systems. Licensed plumbers, HVAC technicians, and fleet maintenance technicians routinely work with this fitting type in both new construction and retrofit applications.

Key Features

• Compression x FNPT end connections allow tool-accessible, no-solder tube-to-pipe joining
• Brass construction provides corrosion resistance for water, air, and compatible fluid service
• 400 psi maximum working pressure rated for demanding fluid and pneumatic lines
• Wide service temperature range: -65 degrees F to 250 degrees F
• Meets DOT FMVSS571.106 and SAE J246 standards for certified brake and fuel line use
• 1/4-18 NPTF thread ensures a pressure-tight mechanical seal at the pipe connection

Compatibility

Designed as an OEM-style replacement or direct-install compression connector for systems using 1/4-18 NPTF female ports with compression tube connections, including brake, fuel, hydraulic, and pneumatic line assemblies that require DOT and SAE J246 certified fittings.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or qualified mechanic following applicable codes such as IFGC, IPC, or DOT brake system regulations. Shut off and depressurize the line fully before disassembling or installing any compression fitting. Do not over-tighten the compression nut, as brass fittings are susceptible to deformation of the ferrule seat. Inspect the tube end for squareness and burrs before seating the ferrule to ensure a proper seal.