One of the best features of some models has not even been documented yet. But, this guide would not be complete without bringing it to your attention. In this modern world that is becoming more and more dominated by technology devices, there is always going to be a reason to implement extra features in certain products. In this case, this is alluding to the USB ports that some designs will integrate. With this feature, you can charge your USB-compatible devices with the battery of the vest.