Samsung Galaxy S4 Active I537 16GB Unlocked GSM 4G LTE Quad-Core Water Resistant Smartphone - Blue GSM 850 / 900 / 1800 / 1900, 3G: HSDPA 850 / 1900 / 2100, 4G: LTE 700 / 850 / 1700 / 1900 / 2100 / 2600 5" Multi-Touchscreen w/ Protective Corning Gorilla Glass 2 Android v4.2.2 (Jelly Bean), Quad-Core 1.9 GHz Krait 300 Processor, Chipset: Qualcomm APQ864T Snapdragon 6, Adreno 320 Graphics 8 Megapixel Camera (3264 x 2448 pixels) ) w/ Autofocus, LED Flash + Front-Facing 2 Megapixel Camera + Video Internal Memory: 16GB (11.2GB user available), 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.