Heli-coil 1185-04CN224S Free Running Insert 4-40 Unc 1000 Pack

Product Description

The HELI-COIL 1185-04CN224S is a tanged, free-running wire thread insert designed to install a full-strength threaded hole in parent materials that are soft, worn, or damaged. Manufactured from 304 stainless steel, it provides corrosion resistance and maintains thread integrity under repeated fastener cycling. The insert carries a 4-40 UNC thread specification with an overall length of 0.224 inches and a 2D length-to-diameter ratio. It ships in a pack of 1000 units, making it a practical choice for production environments and maintenance shops that need consistent thread repair or thread reinforcement at volume.

Free-running inserts are used where a secure threaded connection is needed without a prevailing torque or locking feature. This insert suits applications in aerospace, electronics, industrial equipment, and any assembly where 4-40 UNC threads are tapped into aluminum, magnesium, plastic, or other low-strength base materials. The tanged style is compatible with standard Heli-Coil installation tooling. Machinists, assembly technicians, and maintenance professionals working in production or field repair scenarios are the primary installers.

Key Features

• 304 stainless steel construction for corrosion resistance and durability
• 4-40 UNC thread specification for compatibility with standard inch-series fasteners
• Tanged design for use with standard Heli-Coil tang break-off tooling
• 0.224 inches overall length at a 2D length-to-diameter ratio
• 6-3/4 free coils per insert for full thread engagement
• Pack of 1000 units suited for production and high-volume repair work

Compatibility

Designed as an OEM-style free-running thread insert for use with standard Heli-Coil installation tooling in 4-40 UNC tapped holes.

Installation Notes

Installation requires a properly sized Heli-Coil tap to prepare the parent material and a matching installation tool for the 4-40 insert series. Power down or de-energize any assembly before performing thread repair on components in live electrical or mechanical systems. After driving the insert to the correct depth, use a tang break-off tool to remove the drive tang from the installed insert. Follow the fastener manufacturer and applicable industry guidelines for proper hole preparation and insert seating depth.