1477 Casio Data Bank 150 Illuminator Watch DBC-1500 w/ Casio Band NEW BATTERY | eBay
How to replace the battery in a Casio EDB-610 Calculator Watch - YouTube
DBC-1500] A 90s calculator watch. Never used. Seems to have a metal case. Heavy thick metal band. None of the buttons work. Will crack open again to see what I did wrong