Omega Pocket Watch from 1915

My grandmother has recently decided to give to every of her grandchilds one object that remind us our grandfather.
Knowing that i'm a watch addict, she wants me to have my grandfather's watches. At first, I was really exited and happy, because i don't remember him much (he passed away when i was a little kid) and it was the perfect combination between my passion and my family history.
My grandpa was a Spitefire pilot in the Royal Air Force during the WW2, and i was really honored to wear the watch he had at this time, or the other watches he had at the end of his life - a rolex DD and an omega as far as i know.
Sadly, we're not able to find any of them and that won't be my grandfather souvenir...

In her research, she found some older family watches. Some ladies ones and somes man ones. She doesn't have the family story behind.

Here are the two ladies ones :



She also found an Omega Pocket watch, that appears to be NOS :




- It's a 5 milion serial (so around 1915 / 1916).
- Gold case. No decoration on it (don't have a picture...)

What do you think about it?
Is it a really NOS watch or has it been redone somehow 50 years ago and everyone forgot about it?
Any idea of the value?

Thanks for your help!

I agree that it looks like it wasn't used very much.

As for date, I have a wristwatch with a 3.8m serial number that might imply 1910, but the movement wasn't introduced, according to some Omega books, until 1917. So your watch might be newer than 1916.

That's a nice watch. Treat it well! If you intend to use it, make sure to get it serviced by a competent independent watchmaker. Based on your comments, you're in UK, so Simon Freese might be your choice.

After 50 to 100 years of sleeping in a closet, i’m sure a service could be useful indeed.
About my comments what do you mean? i’m in Switzerland. Do my writings have an English accent? 😁

Beautiful pocket watches! The Omega looks really neat. Probably needs some fresh oil and is ready to be used for sure!

Yup.

Ok. I get it. No hard feelings.
my grandfather was in France and went to England to engage himself in the army.