The 4131 Era: A Technical Examination of the Clean Factory Rolex Daytona Panda 126500LN
There are moments in modern watchmaking when a movement update does more than introduce new parts—it redefines the visual and mechanical language of the watch itself. The transition from Rolex’s Calibre 4130 to the new Calibre 4131 marks one of those moments. And for a reference as culturally embedded as the Daytona, the ripple effects of that evolution extend well beyond the genuine models. The replica world was forced into a structural rethink, because the 4131 changed more than a movement. It changed proportions, dial geometry, surface relationships, and the rhythm of how the chronograph behaves on the wrist. Among…