You’re allowed one guess as to my favourite colour...
What reference is this? Beautiful.
Holy smokes! Is that thing for real? Tell us a more, please. How old is it?
I asked the Seiko museum for information and this was the answer:
"Dear Mr. Xxxx,
It seems to be a #10 line, manufactured from 1931 to 1945.
There are just a few materials we have, we couldn’t find any more.
Thank you for your inquiry.
SEIKO MUSEUM"
I did some research and this watch probably belonged to a Japanese officer captured during the WWII but, obviously, I'm not sure.