Beautifully engraved certificate from the Heli-Coil Corporation issued in 1966-1977. This historic document was printed by the Security-Columbian Banknote Company and has an ornate border around it with a vignette of two allegorical men with the company logo and the United States on the background. This item has the printed signatures of the Company's President and Secretary and is over 25 years old.
Heli-Coil developed the revolutionary inserts that 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 degree internal screw threads that accommodate any standard bolt or screw. In other words, Heli-Coil fixes stripped threads with its patented device. The historic certificate has an ornate blue border with semi nude allegorical figures in front of the United States holding up the Heli-Coil Logo.