The hand-wound calibre L951.1 is an entirely newly developed chronograph movement in classical column wheel design and has a flyback function. With an adjustable shift lever, the exact point of the jumping point of the minutes counter can be set in the assembled movement - an invention for which Lange has received a patent. Also patented is the two-disc mechanism of the big date. The shock protected screw balance makes 18,000 vibrations per hour and is adjusted in five positions. The Swan's neck fine regulation with patented beat adjustment mechanism is mounted on the small balance cock. It is hand-engraved.