Built from the original design used to manufacture the Yale 120 hour movement. Our enhanced version offers: Reset, magnified lens escapement cover, 144 hour maximum locking hours, retrofits most Yale applications requiring a “pocketed” movement, 17-4 PH unbreakable mainspring, left hand standard and adjustable indicator for precise “zeroing” the timelock housing. This movement can replace movements made by S&G, Le Febure, La Gard, Rench, Relhor, Sonceboz and others. The design platform is based on a 25 year standard of manufacture. With proper care, this movement can easily render 50 years of service. This LKM104YL model is built with longer unlocking pin.