Today’s piece is from February 1969, and is Citizen’s ‘Monthly’ version of the Seven Star Deluxe. Using a 5270, 23 jewel calibre from the 52 line-up of automatics introduced in 1965, it features a manually set month display above the 12 o’clock marker as well as the usual day and date complications. The month is set via a small winder at the 2 o’clock position, which is quite easy to move accidentally as you can see from the photo! The Monthly was sold on the Japanese Domestic Market, with all the dial markings you expect, whilst for export markets it was re-badged as the ‘Moon Dater’, lost ‘Seven Star’ and ‘Deluxe’ from the dial and used the 21 jewel variant of the movement. I have seen ‘Moon Dater’ described as a mis-translation by Citizen – it’s a cool name for a watch though 🙂

The Monthly runs at 18,000 beats per hour, can be hand wound and has quick-set date. The case/model number is the older style on mine – ACSS52704 – which tells us not only that it is a 52 movement, but also that it has a hardened mineral glass crystal (i.e. the ‘C’ in ACSS). The later style of case number can be found on these, either 4-521897 or 4-520319. Mine has a black dial – there is a silver dialled version as well:

More info on this, and an earlier Jet automatic Monthly that is much harder to find (with apologies for some missing images, PhotoBucket needs to explain that!):
https://sweep-hand.org/2011/05/20/this-weeks-featured-watch-4-the-monthly/