Yes, they do. I have a Casio clock on my nightstand, it must be from before 2000, if not from before 1995. The display segments are failing, but apart from tha

Yes, they do. I have a Casio clock on my nightstand, it must be from before 2000, if not from before 1995. The display segments are failing, but apart from that: No button broke yet, calendar is still working, so is the alarm.