People who viewed this item also viewed: 136747, 135337, 96569, 20412, 142544
The 4207 is a tiny movement which also uses an equally tiny main spring. Its power reserve is significantly smaller than the 7s caliber which has a bigger main spring. The smaller mass of the oscillating rotor may also mean that automatic winding is less efficient compared to the bigger mass of a typical 7s rotor. Therefore, it makes sense to add a manual wind feature to assist in keeping the main spring fully wound. The 4207 doesn't hack and thus cannot be synchronized to a time source. Seiko decided that this feature probably was not important for the target consumer.
Item created by: Lethe on 2015-08-10 17:31:17
If you see errors or missing data in this entry, please feel free to log in and edit it. Anyone with a Gmail account can log in instantly.