A. Lange & Söhne Caliber L001.1 Watch Movement

Brand	A. Lange & Söhne
Caliber Number	L001.1
Movement Type	Mechanical, manual-wind
In-House?	Yes
Diameter	30.5mm
Height	9.5mm
Total Components	465
Jewels	40
Beat Rate	21,600, 3Hz
Power Reserve	38 hours
Chronograph System	Column wheel
Hand Count	8
Functions	Central hours; central minutes; central double split flyback chronograph seconds; 30 minutes double split chronograph counter at 4:00; small running seconds at 8:00; power reserve indicator at 12:00
Features	Double chronograph, rattrapante, flyback
Country of Manufacture	Made in Glashutte, Germany
Known Models	A. Lange & Söhne Double Split (Refs: 404.032, 404.035) (Add your watch to the comments below…)

The A. Lange & Sohne caliber L001.1 is an in-house mechanical double chronograph movement with a flyback function.

Originally introduced in 2004 in the A. Lange & Sohne Double Split, the cal. L001.1 is the first double rattrapante mechanical chronograph movement in the world.

In the manufacturer’s own words:

“The DOUBLE SPLIT is the worldʼs first mechanical chronograph with a double-rattrapante function. It features two chronograph hands and two rattrapante hands. Both pairs of hands can be stopped separately. Additionally, the stopped rattrapante hands can rejoin the still running chronograph hands. This allows purely mechanical comparative and intermediate time measurements of events lasting up to 30 minutes.”