/fa/ - Fashion

Good day metrosexuals.

tl;dr I inherited a watch from my grandfather and I can't find out what it is.
My dad suspects it is a watch that was given to him in the military during WW2.

If it isn't clear the front says

ASU
MARIN
AUTOMATIC

SWISS MADE

and the back is just

"Stainless steel back, waterproof, shockabsorber, antimagnetic, automatic"

No years, no dates.
It doesn't have a battery instead you shake it to charge it, it keeps time perfectly despite laying in a box for about 40 years.
I was thinking about actually using it, it needs a new strap obviously and the glass is cracked in a couple of places.

But I'm mostly interested in if there are any autists here who would know what watch this is.