The battery is about the size of a normal external hard drive, but weighs a bit more, but this is normal for batteries and technically simply not possible otherwise. The battery is charging my phone (iPhone 6) very quickly, I think in the same league as the big power supply, which is meant for iPads. With the capacity I am very satisfied, I have never reached the limits of the battery, but this can now say anything more precise, because I did not make any extensive testing with the battery but I just used it and not think anything misbehaving. Only charge the battery selbers also takes a while, but probably also with the state of the art not help is solvable. Overall, a great recommendation, especially for the low price!
