Heli-coil A4184-8CN200 Insert M8 X 1.25 Tangless Ss

Product Description

The HELI-COIL A4184-8CN200 is a tangless screw-locking helical coil insert designed to create a strong, vibration-resistant internal thread in a host material. Manufactured from Grade 304 stainless steel with a bright finish, this insert accepts an M8 x 1.25 metric coarse thread and measures 20 mm overall in length, corresponding to a 2-1/2D length-to-diameter ratio. The locking feature holds fasteners securely under dynamic loads and vibration without adhesives. Machinists, maintenance technicians, and assembly professionals install this type of insert to repair damaged threads or to provide a durable threaded interface in softer base materials.

This insert is suited for industrial assembly, MRO thread repair, and OEM manufacturing applications where M8 x 1.25 metric coarse threads are required. The tangless design eliminates the need to remove a drive tang after installation, reducing the risk of loose fragments in assemblies. It is commonly used in aerospace, automotive, mechanical equipment, and general metalworking applications where stainless steel corrosion resistance and consistent locking torque are priorities. The outside diameter ranges from 9.80 mm minimum to 10.35 mm maximum, fitting standard M8 Heli-Coil tapped holes.

Key Features

• Tangless design eliminates post-installation tang removal, reducing assembly debris risk
• Grade 304 stainless steel construction provides corrosion resistance in demanding environments
• M8 x 1.25 metric coarse thread with 20 mm overall length and 2-1/2D ratio
• Locking coil design resists fastener back-out under vibration without adhesives
• Maximum locking torque of 6.00 N/m with a minimum breakaway torque of 0.80 N/m
• Bright finish with 13-1/4 free coils for consistent thread engagement

Compatibility

Designed for use in standard M8 x 1.25 metric coarse Heli-Coil tapped holes following the appropriate insert installation specification for 2-1/2D length inserts.

Installation Notes

Installation requires a properly drilled and tapped hole prepared with the correct Heli-Coil tap for M8 x 1.25 metric coarse tangless inserts. A tangless insert installation tool is required - standard tang-type tools are not compatible. Power down all associated equipment before performing thread repair or insert installation in service applications. Follow the equipment manufacturer and insert supplier torque and installation depth specifications to ensure proper seating and locking engagement.