Swatch Retro Vintage Watch with Case - 1988

Vintage Swatch watch.
I believe it's from around the 1988s.
The battery is dead, so I haven't confirmed if it works.
It's been in storage for a long time.
The front is relatively clean, but...
The back has deteriorated and fallen off.
Other parts may also deteriorate and come off.
The instruction manual is also yellowed.
Please understand the condition.
Thank you.