Will SMG960U1ZKAX work on republic, last 4 letters are not in list?
Yes, probably, depending on where purchased, however you shoulkd consult How to Find a Compatible Unlocked Phone … this Tips & Tricks
by @louisdi provides the full details, as there are exceptions that he has noted
Yes, that phone is compatible.
For those of us who aren’t fluent in SKU, could you tell us what those last four letters represent?
I forget, not everyone was lucky as I was to grow up in a household where my parents came to the US from SKUlandia when they were teens and we spoke SKUish and the English interchangeably at home. I any case, KAX means the phone is black and factory unlocked, other colors will have a letter other than “K”, so for instance BAX for blue. In addition, there is a generic unlocked SKU that ends in XAA.