Unlocked iPhone 4 models will come without a micro-SIM card. (By Daniel Barry/Getty Images)

The unlocked iPhones will let users go to any GSM-based carrier in the world — or just AT&T and T-Mobile in the United States — without a contract. You can get the phones in white or black. The 32GB iPhone will set you back $749.

The phones come without a micro-SIM card, which interested buyers will have to get from a supported carrier. According to Apple’s site, you can’t use an iPad micro-SIM card in the iPhone, and orders can only be shipped within the country of purchase.

Right now, the phones are shipping within three business days.

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