what are the differences? will both versions work the same in the usa? are there regional locks/blocks?
They support somewhat different LTE bands -- in fact the International version supports more bands, though not all the ones needed by US carriers.
3G bands HSDPA 800 / 850 / 900 / 1700 / 1800 / 1900 / 2100 - Global model
HSDPA 850 / 900 / 1700 / 1900 / 2100 - American model
4G bands LTE band 1(2100), 2(1900), 3(1800), 4(1700/2100), 5(850), 7(2600), 8(900), 9(1800), 17(700), 19(800), 20(800), 28(700), 38(2600), 39(1900), 40(2300), 41(2500) - Global model
LTE band 2(1900), 3(1800), 4(1700/2100), 5(850), 7(2600), 12(700), 13(700), 17(700), 25(1900), 26(850), 29(700), 30(2300), 41(2500) - American model
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