If it's a phone with several variants, they will have a different model number for different regions, or even a specific carrier in some cases. For the manufacture date, I've seen LG encode that into their serial numbers. Others may show it in the "about phone" section of the settings menu, under something like a warranty date. There isn't one set of rules for this, so it would be helpful if you could let us know which phone you have. Then we may be able to give you a more specific answer.