A Jet movement is a ring rotor one that I really like a lot. Rumor has it that Citizen chose to replace this movement with a central swinging rotor, even though the circular rotor one was of a better quality, because the later was easier and cheaper to produce. Others say that the Jet were not as reliable, but I strongly doubt that, and others believe that the change was due to a growing trend for slimmer watches that were not a perfect match for this kind of movements. The Jets was produced starting from October 1961 up to about 1967. The first was a simple three hands non date one and the last, the Auto Dater Seven, with a date and day feature. The most impressive one is the 39 Jewels Super Auto Dater.
In fact the first automatic Citizen calibre was a “normal” one with a centrally attached swinging rotor that was made for only about 2 years. The Jet (so, the second type of Citizen automatic movements) are all beating at 18,000 bph and have a power reserve of about 45 hours. These movements, as stated , are automatic but (most of them) can be manually winded too. The rotating ring has 4 or 6 screws. The thing I like the most it the beautiful sound that the rotor is making when rotating, smooth, loud, mechanic.
Here you can find a few watches powered by these amazing movements.
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