R.I.P. my GA-100 π After 10 years of service it died because of water after a battery change by a shop. looking forward to buying a gw 7900 : r/ gshock
Casio G-Shock Digital Analog Watch Men Black Red 5081 GA-100 200M New Battery | eBay
How to Replace a G-Shock GA201-1A Battery - iFixit Repair Guide