Samsung X640 Unlocked Cell Phone--International Version with Warranty (Silver) 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. Tri-band GSM cell phone compatible with 900/1800/1900 frequencies and GPRS capabilities VGA digital camera with 4x digital zoom and video capture Supports up to 1,000 contacts and 200 SMS messages Up to 3.5 hours of talk time, up to 220 hours (9+ days) of standby time