Here you go Hanzo, you can read all about it.starting at the bottom of page 1. https://support.casio.com/storage/en/manual/pdf/EN/009/qw2632.pdf
As a prepper, I have thought about how we would tell time after the SHTF! ALL of the electric and battery powered clocks and watches will be dead. The surviving smartphones and computers will be too valuable to carry around as time pieces. Mechanical, solar and movement powered watches will be invaluable, as will wind-up clocks!
If things are at that stage, no need time keeping per se. The sky will tell you how much light you have.
Worth keeping some in storage. Affordable, easy, rugged, dependable... https://www.amazon.com/dp/B0DTB5641V/?tag=survivalmonke-20 The Casio AE-1600H Series 10 year battery (CR2032) LED backlight with afterglow 100m water resistance Bold large face design 1/100-second stopwatch Countdown timer with auto-repeat 5 multi-function alarms (including 1 snooze alarm), and hourly time signal. Supports both 12-hour and 24-hour formats Very accurate, ±30 seconds per month Or if you want something about 10 Dollars less, https://www.amazon.com/dp/B09Z4T3C8N/?tag=survivalmonke-20 The Casio W737HX Series is also a fine choice.
For many years now it's been just this Maratac large Pilot. No batteries, no frills. Just big and clear.