The good thing about the device is the I-Smart function. The device adjusts the amperage smartphone etc..
Each unit is therefore charged as soon as possible. Max 2.4 A
For a long holiday trip highly recommended, so you have to not always upload alternate with the smartphone, or the like.
One complaint I have though.
The device can read it out very far from the "cigarette lighter".
There are already flatter on the market that even have 4 USB ports. I'd rather take a number 2 USB which ensure that retracts completely.
But all in all, the device does the job