Samsung G313ML/DS Galaxy Ace 4 - Unlocked (Black) 2G: GSM 850 / 900 / 1800 / 1900, 3G: HSDPA 850 / 1900 / 2100 4" TFT Display Capacitive Multi-Touchscreen Android v4.4.2 (Kit Kat), Dual-Core 1.0 GHz Processor 5 Megapixel Camera (2592 x 1944 pixels) w/ Autofocus, LED flash + Front-Facing VGA Camera Internal Memory: 4GB, 512 MB RAM + micro SD Slot Expandable up to 64GB 2G: GSM 850 / 900 / 1800 / 1900, 3G: HSDPA 850 / 1900 / 2100^4" TFT Display Capacitive Multi-Touchscreen^Android v4.4.2 (Kit Kat), Dual-Core 1.0 GHz Processor^5 Megapixel Camera (2592 x 1944 pixels) w/ Autofocus, LED flash + Front-Facing VGA Camera^Internal Memory: 4GB, 512 MB RAM + micro SD Slot Expandable up to 64GB Unlocked cell phones are compatible with GSM carriers like AT&T and T-Mobile as well as with GSM SIM cards (e.g. H20, Straight Talk, and select prepaid carriers). Unlocked cell phones will not work with CDMA Carriers like Sprint, Verizon, Boost or Virgin.