The A1864 is sold by Apple as the SIM-free model and is typically used by Apple for replacement devices. The A1864 is the GSM+CDMA model and works on pretty much any carrier, including Verizon and Sprint. The A1897 is the GSM-only version, sold as the carrier model for AT&T and T-Mobile, and won’t work fully with CDMA networks. Read more
Buying an Unlocked iPhone? Read this first:
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