Samsung Galaxy S II LTE i727R Quad-band GSM Cell Phone - Unlocked 2G Network - GSM 850 / 900 / 1800 / 1900 3G Network - HSDPA 850 / 1900 / 2100 Chipset - Qualcomm MSM8260 Snapdragon 4G Network - LTE 700 MHz OS - Android OS, v2.3.5 (Gingerbread)