Samsung Galaxy Ace Q SGH-I827 Unlocked 3G Phone w/ Slide-Out Keyboard and 3.2" Touch Screen 2G: GSM 850 / 900 / 1800 / 190, 3G: HSDPA 850 / 1900 / 2100 3.2-inch Multi-Touchscreen + Slide-out QWERTY Keyboard Android OS, v2.3 (Gingerbread) 3.15 Megapixel Camera (2048 x 1536 pixels) + Video Internal Memory: 4 GB, 512 MB RAM, 1.8 GB ROM + microSD Slot Expandable up to 32GB 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.