Samsung X506 Unlocked Cell Phone--U.S. Version with Warranty (Black) 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. Quad-band GSM cell phone compatible with 850/900/1800/1900 frequencies and GPRS/EDGE capabilities Entry-level clamshell phone for voice communication and SMS/MMS messaging Organizer with calendar, world clock and unit converter; dual displays Up to 5 hours of talk time, up to 250 hours (10+ days) of standby time