Unlocked Doogee550 DG550 5.5" Android 4.4 Octa-core 1+16GB Smartphone (US Standard Black) Screen: 5.5 inch IPS OGS 1280*720 CPU: MTK6592 1.7GHz Octa Core 5.0MP Front Camere+ 13.0 MP Back Camera Super Thin and Simple Metal Design - Only 6.5 mm or 1/4 inch Thick! DOOGEE DG550 5.5 Inch Android 4.2 MT6592 1.7GHZ Octa Core 13.0MP Camera 1GB/ 16GB Dual Sim 3G Smart Cellphone (Black) Network&#xFF1A;WCDMA 3G (HSDPA 21Mbps,HSUPA 5.76Mbps), Support WIFI AP ,WCDMA 3G (HSDPA 21Mbps,HSUPA 5.76Mbps), Support WIFI AP,EDGE,GPRS,WAP 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.