CASIO CasioTron CASIOTRON Watch Battery replaced, operation confirmed. The small light bulb also lights up properly. This is an original CASIOTRON. It's a model from about 50 years ago. The CASIOTRON is CASIO's first wristwatch. Despite that, it has a date function and a stopwatch. The body, which looks like it was milled from metal, the black face, and the gold logo are very cool, and it's an excellent design that still holds up today. I don't think you'll find many fully functional ones. There is a feeling of use, scuffs, and scratches, but I think the condition is not bad for an item from that time. The belt is the valuable original. The wrist size is about 18cm.