+33 (0)1 40 04 92 30 Lun - Jeu 7h30 - 17h30 / Ven 7h30 - 16h 37, Avenue de Saint-Mandé 75012 PARIS
+33 (0)2 48 50 18 10 Lun - Jeu 8h - 17h / Ven 8h - 16h Rue du Minerai 18570 La Chapelle-Saint-Ursin
ISO 9001 since 1998


The problem

J. Lanfranco has long been recognized by military contractors for a wide range of applications: Leclerc tanks, computer and electronic caissons for Lockheed Martin, high-speed winches for Navy helicopters. J. Lanfranco’s ESL self-locking nuts ensure the performance and reliability of critical military bolted assemblies.

Armed equipment installed on military vehicles must not only resist high vibrations during service, but also not require maintenance and servicing while in the field.

A problem frequently encountered during these interventions is the seizure of stainless steel. This is the case of the machine gun sight. Due to the high vibrations generated on large vehicle-mounted calibers, the viewfinders must be adjustable in the field and this adjustment must withstand intense service conditions.

The solution

The ESL nut has been tested and approved as it ensures:
– An independent lock of the tension bolt
– The ability to withstand shocks
– The absence of insert that could break
– High thermal resistance and impermeability to corrosive and chemical agents
– No seizing or damage to bolt threads


The benefits of our ESL nut for our customers were immediate:

  • All these factors allow the weapons to operate accurately without incident. They also guarantee multiple adjustments without deterioration of the threaded rod of the visors.

About us

Founded in 1974, J. Lanfranco & Cie specializes in the manufacture of high-end self-braked nuts and safety fasteners. ESL and ERM have been on the market for more than 40 years, in the most extreme conditions.