I am a lot of walking on the road and have no use for heavy chunky Power Bank and then the charger cable ... So I decided for this product.
It is so small that I hardly notice in my back pocket. I have always with you, because you never know when you can use another phone charge. The great thing about this external battery is that you really do not need more charging cable. Everything is already installed and can be used directly.
The Power Bank is indeed only almost as thin as a credit card but the charge has to be stored somewhere ...
For a cell phone charging in between I would recommend this device!