The caliber inside the Lange 1 was among Lange's first ever developed, meaning it has been a quarter century since the design of this caliber began. The men and women of Glashütte felt it was time, though no one asked for it, to give its most iconic model an internal upgrade. So, beginning with this model year, the Lange 1 will house caliber L121.1, the 50th new caliber since its re-birth two decades ago. Lange is quick to point out that the goals and aesthetics of this new caliber are indeed the same as the original, this is not merely an upgrade, but a whole movement.