Proto J3768 Open End Flare Nut Wrench 1/2 X 9/16 Inches

Product Description

The PROTO J3768 is a double-end open end flare nut wrench designed for gripping flare fittings and line nuts on refrigerant, fuel, and hydraulic lines. It features a 6-point contact design that reduces rounding of soft brass and steel fittings. The wrench spans 1/2 inch on one end and 9/16 inch on the other, with a 7-1/2 inch overall length (OAL) that provides adequate leverage in confined service bays and equipment rooms. Constructed from steel with a chrome finish, it resists corrosion and cleans easily. This tool is suited for HVAC technicians, plumbers, and automotive mechanics who regularly work with flare-type line connections.

Flare nut wrenches are the correct tool for tightening and loosening line nuts on refrigerant piping, fuel lines, brake lines, and hydraulic connections. The open end slot allows the wrench to slide over tubing and seat around the fitting, minimizing the risk of rounding the nut compared to a standard open end wrench. The 1/2 inch and 9/16 inch sizing covers common fitting sizes found on residential and light commercial HVAC systems, plumbing supply lines, and related mechanical systems. This wrench is appropriate for field service kits and shop tool inventories alike.

Key Features

• Double-end design provides two sizes in one tool: 1/2 inch and 9/16 inch
• 6-point open end contact reduces rounding on flare fittings and line nuts
• 7-1/2 inch overall length for leverage without excessive bulk
• Steel construction with chrome finish for corrosion resistance and easy cleaning
• Open end slot allows placement over tubing before seating on the fitting

Compatibility

Designed for use with 1/2 inch and 9/16 inch flare-type line nuts and fittings commonly found on refrigerant lines, fuel lines, and hydraulic connections in residential and light commercial mechanical systems.

Installation Notes

HVAC technicians and plumbers should use flare nut wrenches exclusively when tightening or loosening line nuts to avoid deforming the fitting hex. Slide the wrench over the tubing before engaging the nut. Do not use extension bars or pipe cheaters on this tool, as overloading can damage both the fitting and the wrench. Follow applicable codes and manufacturer torque guidance for the specific fitting type being serviced.