Heli-coil 1084-4CN080S Free Running Insert M4 X 0.7

Product Description

The HELI-COIL 1084-4CN080S is a tanged free running wire thread insert designed to create durable, wear-resistant internal threads in tapped holes. Manufactured from 304 stainless steel, this insert accepts M4 x 0.70 metric coarse threads and measures 8.0 mm (0.315 inches) in overall length, placing it in the 2D length-to-diameter ratio class. It ships with a tang for installation with a standard tang-break tool. Machinists, maintenance technicians, and MRO professionals use these inserts to repair stripped threads or to reinforce threads in soft-base materials for long-term fastener retention.

This insert is suited for metric coarse thread applications in precision assemblies, light machinery, and threaded hole repair work. The M4 x 0.70 specification matches standard metric coarse pitch, making it a common choice for electronics enclosures, small mechanical assemblies, and equipment maintenance operations requiring thread restoration to OEM dimensions. It installs into a properly tapped STI (Screw Thread Insert) hole using a HELI-COIL installation tool and tang-removal tool.

Key Features

• M4 x 0.70 metric coarse thread - matches standard STI tap requirements
• 8.0 mm overall length (0.315 inches) - 2D length-to-diameter ratio
• 304 stainless steel construction - corrosion resistant for demanding environments
• Tanged design - compatible with standard HELI-COIL installation drivers
• 8-5/8 free coils - provides consistent thread engagement across the insert length

Compatibility

Designed for use in any application requiring a tanged free running insert with M4 x 0.70 metric coarse threads and a 2D insert length, installed into an STI-tapped hole of the appropriate drill and tap specification.

Installation Notes

Installation requires a correctly sized STI tap and a HELI-COIL installation tool matched to the M4 insert series. Ensure the base material hole is tapped to the full insert length before driving the insert. After seating, break the tang using the appropriate tang-break tool and remove it from the hole. Follow applicable shop safety practices and confirm thread gauge acceptance before returning the fastener to service.