Electro-luminescent backlight: Auto light switch, afterglow. World time: 29 time zones (27 cities), city code display, daylig… | Casio uhr, Casio digital, Sportuhr
Casio MD 310 Mod. 1389 AUTO LIGHT "Diver´s work | eBay
Casio Protrek Autolight testing on daylight & Dark room - YouTube