This tidy little number from the very early days of Casio’s watch division is just about their simplest-ever module – 3.1 digit time with a PM indicator, date, and seconds. Researching this one took a while, because there’s nothing specific about it; info had to be inferred. To complicate matters, it seems there was quite some variation on the same module back in the day, with what appears to be different cell retention in the only pic I could find of a #6 module, and possibly even different button locations employed on other models with this module. Incomplete tables exist of early models and modules and cell types, and every other listing for module #6 shows it takes a 309/393/SR753/SR754 cell (7.9×5.4mm) but it’s currently rocking a 384/392/SR41/SR736 cell (7.9×3.6mm), and I’m not sure there’s room for the extra 1.8mm, but perhaps… Anyway, the module sits in a lovely little screwback stainless steel case with its original bracelet in great condition, ready for a wrist up to 18cm. The crystal has some scratches, and the case has a couple of slight dents on the back edge. A lovely detail on this one is that the screwback ends up perfectly clocked when tightened!

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