Nixie tubes type IN12 are in sockets, not soldered. Single button for access all features (push and rotate).
Precise internal chip for accurate timekeeping (independent of mains frequency). Date format dd:mm:yy/mm:dd:yy. 10 brightness levels (including 0 for tubes off). Daily schedule with 4 intervals for auto-adjust brightness (including 0 if you want to stop tubes where you are not at home for example). Daylight Saving Time for Europe/US/disabled.
Battery backup (CR2032 in socket). Other special designs at your request, please drop me a line and maybe I'll make your dream clock!