Heli-coil A3585-04CN224 Screw-locking Insert 4-40 Unc

Product Description

The HELI-COIL A3585-04CN224 is a tangless screw-locking wire thread insert designed to create strong, vibration-resistant threaded holes in parent materials that require durable fastener retention. Built from Grade 304 stainless steel with a bright finish, this insert accepts 4-40 UNC fasteners and provides a 2D length-to-diameter ratio with an overall length of 0.224 inches. The locking feature is achieved through a deformed coil that applies radial pressure on the mating screw thread, resisting loosening under dynamic loads. Machinists, assembly technicians, and maintenance professionals install these inserts using a standard installation tool in pre-drilled and tapped holes.

This insert is suited for applications where a reliable locking thread is needed in small-diameter fastener locations, including electronic enclosures, instrument panels, precision equipment, and light mechanical assemblies. The tangless design eliminates the need for tang removal after installation, streamlining the assembly process. Its stainless steel construction makes it appropriate for environments where corrosion resistance is a priority.

Key Features

• Tangless design - no tang removal step required after installation
• Grade 304 stainless steel construction with bright finish for corrosion resistance
• 4-40 UNC thread size with 2D length-to-diameter ratio
• Maximum locking torque of 48 oz-in with a minimum breakaway torque of 10 oz-in
• 6-3/4 free coils for consistent thread engagement and locking performance
• Minimum outside diameter of 0.144 inches, maximum outside diameter of 0.159 inches

Compatibility

Designed as an OEM-style replacement or new-installation thread insert for tapped holes requiring 4-40 UNC internal threads with a 2D insert length.

Installation Notes

Installation requires a properly tapped parent hole sized for a Heli-Coil 4-40 insert and a compatible tangless installation tool. Power down or de-energize any assembly before performing thread repair or insert installation in electrical or electronic components. Follow applicable assembly standards and torque guidelines for the parent material being used. Do not attempt to install this insert without the correct installation tool, as improper installation can damage the coil or parent material.