I had something similar about 30 years ago, but mine was black/plastic, not silver/metallic. Buttons were a bit different, too. But it was a Casio and it had all kinds of functions like a calculator and phone/address book.
I never had to change the battery, but I wonder if changing the battery wiped the storage. I never tried.
On one hand, I wouldn't mind having another. I always thought that thing was so cool. That said... I like my Apple Watch (S10). I don't care that it's not a "nice watch." I'm not a watch guy. (I'm here because I browse /all and saw a familiar watch.) (Also, I do appreciate a nice watch.) I like the data, the health data it records and the data, like my notes, it lets me access.