Samsung Galaxy Tab 4 10.1" T531 3G + Wi-Fi 16GB Unlocked GSM Quad-Core Android 4.4 (KitKat) Tablet PC - White 2G: GSM 850 / 900 / 1800 / 1900, 3G: HSDPA 850 / 900 / 1900 / 2100 10.1" TFT Display Capacitive Multi-Touchscreen Android v4.4.2 (KitKat), Quad-Core 1.2 GHz Processor 3.15 Megapixel Camera (2048 x 1536 pixels) + Front-Facing 1.3 Megapixel Camera Internal Memory: 16GB, 1.5GB RAM + microSD 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.