Heli-Coil® inserts are precision formed screw thread coils of stainless steel wire having a diamond shaped cross section. When they are installed into Heli-Coil® tapped holes, they provide permanent conventional 60' internal screw threads that accommodate any standard bolt or screw. All related tooling such as STI Taps, hand and power installation tools, gages and tang break-off tools are also available. Typical Applications would include: Automotive,Communication, Aerospace, Military and the Defense industries.

Heli-Coil® Standard and Screw-Lock Inserts are the original - and have an extensive background of tension, torque, shear, vibration and fatigue tests conducted by the American industry's leading companies as well as the U.S. Military. Successful applications in the fields of aviation, electronics, industrial, automotive and military equipment provide a wealth of experience and confidence in the performance and reliability of Heli-Coil® Inserts.

In the free state they are greater in diameter than the tapped hole into which they are installed. In the assembly operation the torque applied to the tang reduces the diameter of the leading coil and permits it to enter the tapped thread. When the torque or rotation is stopped, the coils expand with a spring-like action anchoring the insert permanently in place against the tapped hole. No staking, locking, swaging, keying, nor interference fit is required to retain Heli-Coil Inserts, thereby eliminating stress concentration in the parent material. The Heli-Coil Insert automatically adjusts itself, radially and axially, to any expansion or contraction of the parent material.