6223--925,k SN, I.54, "Brevet +"/"Modele Depose" case--posted by tomvox1

Note: 10.5’ 17-jewel Super Balance manual wind movement. The French case engravings "BREVET+" (Swiss Patent)/”MODELE DEPOSE” (Registered Design) were only used by Rolex for a short time in the mid-1950s. Similarly, the mysterious "18" stamp inside the caseback is only found during this period.