Phone marked as EU Version etc.?

[AC Question]

I'm thinking of buying Oneplus 3T and on Geekbuy you can choose all those version like China, US, EU, Package B etc. On the other hand on Banggood you have nothing to choose yet it's cheaper price. Can someone explain me what those EU, China, Package B means when buying a phone? What should I personally choose? I live in Croatia, Europe.

Thank you.

 

[belodion]

There are different regional versions of phones because of different firmware and firmware updates, sometimes different radio bands, occasionally different hardware. The EU version sounds right for you, but check carefully beforehand.
Also, paying less is of course not always wise.