The Langendorf 1146 watch movement was jointly developed by Hamilton-Buren, Breitling, and Heuer during the period from 1969 onwards. It features the Dubois-Depraz 8510 module on a modified Buren 1281 base. Noteworthy technical elements include a crown positioned at 9 o'clock, a micro rotor, and a double excenter regulator for curb pins and stud carrier. The indirectly driven minute function enables a low profile design. In terms of functionality, it offers an automatic chronograph with durations of 60 seconds, 30 minutes, and 12 hours, all cam-switched. Additionally, it incorporates a date function that can be set by changing the 21-24 hour marker.