Heli-coil 1185-4CN500S 1/4-20 Unc Threaded Insert 500 Pack

Product Description

The HELI-COIL 1185-4CN500S is a free-running wire thread insert designed to create strong, wear-resistant internal threads in parent materials that would otherwise strip or fail under load. It installs into a pre-tapped STI (Screw Thread Insert) hole and locks into the parent material via tang engagement. The insert is coiled from 304 stainless steel wire for corrosion resistance and durability. At 0.5 inches overall length with a 2D length-to-diameter ratio and 8 free coils, this 1/4-20 UNC tanged insert is suited for medium-duty threaded repair and original assembly work across a wide range of industrial and mechanical applications.

This insert is commonly used in maintenance, repair, and original equipment manufacturing where thread integrity is critical. Applications include aluminum housings, castings, plastic assemblies, and thin-wall components where a standard tapped thread lacks the pull-out strength required. It is appropriate for use in HVAC equipment chassis, electrical enclosures, plumbing valve bodies, and general mechanical assemblies. This package contains 500 inserts, making it well suited for production runs or high-volume service environments.

Key Features

• 1/4-20 UNC thread size for broad compatibility with standard inch-series fasteners
• 304 stainless steel construction resists corrosion in wet or chemically active environments
• Tanged design allows installation with standard HELI-COIL insertion tooling
• 0.5 inch overall length with 2D length-to-diameter ratio and 8 free coils
• 500-count package supports production or high-frequency service use

Compatibility

Designed for use in any parent material prepared with the appropriate 1/4-20 UNC STI tap. Requires a matching HELI-COIL installation tool and tang break-off tool for proper installation.

Installation Notes

Installation should be performed by a qualified technician familiar with thread insert procedures. The parent material must be drilled and tapped to the correct STI specification before the insert is installed. Use the proper HELI-COIL insertion tool to wind the insert into the tapped hole to the correct depth. After seating, break off the drive tang using the appropriate tang break-off tool to complete the installation.