Heli-coil A4184-8CNW160 Screw-locking Insert M8 X 1.25

Product Description

The HELI-COIL A4184-8CNW160 is a tangless screw-locking helical wire insert designed to create a strong, vibration-resistant threaded hole in parent materials that require reliable fastener retention. Manufactured from Grade 304 stainless steel with a dry film lubricant finish, this insert accepts an M8 x 1.25 metric coarse thread and provides a 2D length-to-diameter ratio at 16 mm overall length. The coiled design expands on installation to grip the parent bore, while the locking coils resist fastener back-out under dynamic load. Maintenance technicians, machinists, and field service pros use this insert for thread repair and new-hole applications in metal assemblies.

This insert is suited for applications where corrosion resistance and secure thread engagement are required, including industrial equipment, marine hardware, automotive assemblies, and structural components exposed to vibration or repeated fastener cycling. The tangless design eliminates the need for tang break-out after installation, reducing installation steps and preventing loose tang fragments inside enclosed assemblies. It is compatible with standard HELI-COIL tangless installation tooling for M8 x 1.25 threads.

Key Features

• Tangless design removes the need for a tang break-out step, keeping assemblies free of debris
• Grade 304 stainless steel construction resists corrosion in wet or chemically active environments
• Dry film lubricant finish eases installation and reduces galling during thread engagement
• Maximum locking torque of 6.00 Newton-meters provides positive fastener retention under vibration
• Minimum break-away torque of 0.80 Newton-meters ensures controlled removal without damaging the parent bore
• 2D length-to-diameter ratio with 10-1/4 free coils delivers full thread engagement in limited-depth applications

Compatibility

Designed for use with standard HELI-COIL tangless installation tools sized for M8 x 1.25 metric coarse threads. Suitable for installation into tapped holes in ferrous and non-ferrous parent materials wherever a screw-locking helical insert of this thread size and length is specified.

Installation Notes

Installation requires a properly sized tang-drive or tangless installation tool and a correctly tapped parent hole per HELI-COIL tap specifications for M8 x 1.25. Ensure the parent bore is clean and free of chips before driving the insert. Use only the recommended tangless installation mandrel to avoid distorting the coil geometry. Follow the assembly manufacturer guidelines and applicable torque specifications for the fastener being used with this insert.