Samsung Galaxy J1 4G LTE White Smartphone - GSM Unlocked DOES THIS DEVICE NEED A SIM CARD: Yes it does Being that this device is GSM unlocked it will work on any GSM Network with a Nano size SIM Card The sim card does not come included, you will need to contact your Network Provider to acquire your complimentary Nano Sim card (Free from most Carriers with activating of an account). WHAT FREQUENCIES DOES THIS DEVICE SUPPORT: (GSM 850, 900, 1800, 1900 MHz) (UMTS: 850, 2100 MHz) (LTE (FDD) Bands 1, 2, 3, 4, 5, 7, 12) HOW LONG CAN I EXPECT THE BATTERY TO LAST ME: Well the battery size is 2050 mAh (Removable) which in a Usage time frame means 10 solid hours of streaming at 4G LTE speeds as well it has a Standby time of up to 240 hours before you need to recharge the battery. WHAT CAN I EXPECT OUT OF THE BOX: Well the J1 comes out of the box running Android 6.0 with a Quad-core, 1300 MHz processor as well it has 8GB Internal storage (5.6 Avail to user) 1GB RAM 5MP with Flash on the main rear Camera + 2MP Selfy camera and all weighs a mere 4.62 Oz. WHAT DOES UNLOCKED REALLY MEAN: Unlocked devices are compatible with GSM carriers the kinds that Use SIM Cards for Service like AT&T and T-Mobile as well as with GSM SIM cards (e.g. H20, Straight Talk, and select prepaid carriers) Unlocked Devices will not work with CDMA Carriers the kinds that dont use sim cards for service like Sprint, Verizon, Boost or Virgin (contact your network provider prior to purchasing for verification that they support GSM frequencies).