… Depending on the type of watches either leather, rubber or metal straps are attached on the watches…

… testing the chronographs: start, stop and reset …

… the machine can test up to ten chronographs at a time …

… checking the waterproofness …

… the waterproofness is checked by building up a vacuum. If the watchcase has been assembled correctly no air can escape out of the case …

… this watch is waterproof …

… when closed a vacuum is produced …

… final quality control. Every detail is checked; every scratch on the case is detected …

… my photograph shows the Zenith Pilot Montre d’Aéronef Type 20 …

… some little details have to be rechecked to assure a top quality …

… the chronographs after testing their functions …