What would you call a Crystal Seven that doesn’t have a mineral glass crystal? Well, ‘Plastic Seven’ doesn’t have much of a ring to it, so let’s try ‘Super Flat’ instead! Still a slightly odd choice, but the name reflects the slim nature of the 52 movement compared with earlier automatics. Today’s piece was made in July 1966, (unrelated info – the month England won the World Cup 🙂 ) and other than the plastic crystal, it is the same as its more expensive Crystal Seven sibling. The model/case number is APSS52703 – the Crystal Seven version was ACSS52703. The movement is the 23 jewel version of the 5203 calibre, which was produced with a variety of jewelling. It runs at 18,000 bph and has a quick-set date, along with hand winding of course which Citizen provide in most of their movements. This one is running very well:

More info here: https://sweep-hand.org/2014/05/04/this-weeks-featured-watch-59-super-flat-seven-23j/