Fra Apple sine hjemmesider, hvor man kan velge T-mobile (unlocked) står det følgende;
If you buy iPhone for T-Mobile, it will arrive with a nano-SIM card already installed that you can activate by visiting an Apple Retail Store or a T-Mobile store or by calling T-Mobile. When you travel internationally, you can use a nano-SIM card for iPhone 5s from a local GSM carrier. The unlocked iPhone 5s model is A1533 (GSM). For details on LTE support, see
http://www.apple.com/iphone/LTE.
Altså; "The unlocked iPhone 5s model is A1533 (GSM)."
Man vil derfor kunne bruke en ulåst iPhone 5s kjøpt fra USA i Norge