I replaced the battery in a customer’s watch - one of many that she owns, not one of which was working. It’s a world-famous “Vivani” brand 😉 three-hander with a Chinese case and a claimed Japanese quartz movement (it did have a Japanese battery). The battery was an SR626SW, which I replaced with an Eveready 377 (same size, way simpler numbering system). The back of the case has a strange bumpy texture and I can’t imagine any reason for that, since nobody will see it under normal circumstances.
Size comparison with my 35.5 mm Seiko:
It’s all about the bling, apparently, not that there’s anything wrong with that.