I wouldn't call myself experienced with NOS watches, but here are a few things to look out for.
1. To be NOS, the watch needs to have all the pieces with which it was originally delivered. This generally would include a hang tag with the model number and possibly the movement serial number that matches, instruction book, guarantee certificate (some have matching serial numbers), signed buckle, signed strap or bracelet, and both inner and outer boxes.
2. One can assume that the oils in a 50 year old watch that has never been worn would have dried up decades ago. At the very least, a raw NOS watch should be difficult, if not impossible to wind. Nor should it be wound until serviced, and newly oiled.
3. Something that is particular to Omega is the colored wax on back of the case.
View attachment 283779
This was done to prevent scratches from normal handling, like in a jewelry store. Some older models had paper stickers on the back instead.
View attachment 283780
If you don't have all the toys it isn't a complete set and likely not NOS.
gatorcpa
Click to expand...