Sony Ericsson Z300a Unlocked Cell Phone-U.S. Version with Warranty (Granite Gray) This unlocked cell phone is compatible with GSM carriers like AT&T and T-Mobile. Not all carrier features may be supported. It will not work with CDMA carriers like Verizon Wireless, Alltel and Sprint. Dual-band GSM 850/1900 cell phone with GPRS data capabilities Clamshell phone with internal screen and analog clock on exterior Speakerphone; organizer; access to text and picture messaging; 650 KB internal memory (no expansion) Up to 5.5 hours of talk time and 250 hours of standby