This is a fantastic product! I let my phone die completely and this external battery charged it full in about 1 – 1 1/2 hours and the external battery still had 75% life left. I was extremely impressed at its longevity and ability to keep my phone going. The LED’s that let you know the life left in the unit are really dim and in direct light they can not really be seen but that is actually a good thing because they don’t draw a lot of power from the unit giving it a much longer life. There is a touch sensitive button (the silver section on the unit) that you can turn the unit on and off with. The package came with the only two things you need, the unit itself and a USB/micro USB cable. The cable is used for charging the external battery and the phone depending on which slot you insert it into. I love that about the unit because I don’t have to keep up with extra cables or wall chargers. In the winter we sometimes lose power anywhere from a few minutes to several days depending on the severity of the storm and now I can keep our phones charged in case of an emergency. There are larger external batteries but this size was perfect for us as we only have two phones in the house, if you have 4-5 phones I would recommend one of the larger sizes like the 11000mAh to ensure you can keep everything running with any issues. Great on trips also if you have a 12v adapter for your car.