Blackberry Z10 STL100-4 16GB Unlocked GSM / OS 10 Smartphone - Black 2G: CDMA 800 / 1900, 3G: HSDPA 900 / 2100, 4G: LTE 700 MHz Class 13 4.2" Capacitive Multi-Touchsscreen BlackBerry 10 (upgradable), Dual-Core 1.5 GHz Krait Processor, Chipset: Qualcomm MSM896 Snapdragon, Adreno 225 Graphics 8 Megapixel Camera (3264 x 2448 pixels) w/ Autofocus & LED Flash + Front-Facing 2 Megapixel Camera Internal Memory: 16GB storage, 2GB 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.