Parker 41FS-6 Brass Flared Short Nut 3/8 in Od 5/8-18 Unf

Product Description

The PARKER 41FS-6 is a brass short nut designed for 45-degree flared tube connections in fluid and refrigerant piping systems. It accepts a 3/8 inch tube OD and threads onto mating fittings with a 5/8-18 UNF thread. The brass construction provides corrosion resistance and reliable sealing in both low- and high-pressure service. Rated to 1000 psi working pressure and a maximum working temperature of 250 degrees F, this nut suits demanding mechanical, HVAC, and refrigeration applications. At 1.0 inch overall length, it fits in tight plumbing runs where a standard long nut would interfere with adjacent components. Licensed plumbers, HVAC technicians, and refrigeration mechanics are the primary installers.

This short nut is used wherever 45-degree SAE flare connections are required in residential and light commercial systems. Typical applications include refrigerant line sets, fuel gas tubing, hydraulic plumbing, and general fluid-handling assemblies that specify SAE J512 or SAE J513 flare fittings. The compact length suits instrument tubing, control lines, and service valve connections where space is restricted. It is sold individually but must be ordered in multiples of 5 per manufacturer minimum order quantity.

Key Features

• 45-degree flare end connection compatible with SAE J512 and SAE J513 standards
• 5/8-18 UNF thread for positive engagement with standard flare fitting bodies
• Brass material resists corrosion in refrigerant, fuel gas, and water service
• 1000 psi maximum working pressure for high-pressure plumbing and refrigeration lines
• 250 degrees F maximum working temperature for broad service range
• UL Listed — meets recognized safety and performance standards

Compatibility

Designed as an OEM-style replacement or new-installation short nut for 3/8 inch OD tube flare connections conforming to SAE J512 and SAE J513 flare fitting standards.

Installation Notes

Installation should be performed by a licensed plumber, HVAC technician, or qualified refrigeration mechanic. De-pressurize and purge the line before disassembling any flare connection. Ensure the tube end is properly flared to the correct 45-degree angle with a calibrated flaring tool before seating the nut — a misformed flare is the most common cause of joint leakage. Do not overtighten; tighten to snug plus a small additional turn, consistent with SAE flare joint practice, without applying force beyond hand-tight plus standard wrench engagement.