Here's the pic:
Let's say I'm Russian, and that I'm now for holidays or business in Cairo...
I let my Home time on the main dial, and I just use the upper crown to adjust the local time where I am, the hour appearing on the small dial...
When I come back to Russsia, I use the upper corwn to put my home time at 12, and the local time will be automatically set, as the 24 hours disc is coupled to the small dial...
Am I clear in my explanations????
BTW, you should contact your AD to get a manual owner....
Best.
Nicolas