Hi @HelloMate.
All the user manual states is the following :-
Plug the charging cable into the USB port on your computer, a UL-certified USB wall charger, or another low-energy charging device.
Is there a reason why you need to know the detailed specifications? As this is predominantly a user based forum, it's unlikely anyone here will know the definite answer. I use an old iPhone 4s charger to charge mine (as I know its low power) and haven't had any problems.
Best Answer