fpp is correct. The cable looks far too simple to employ any feedback from tablet to USB and it's unnecessary anyway. It's going to draw what USB provides which is well under upper safety margin. IMO the cable will make a nice accessory for your laptop PC moreso than the tablet in most cases. I saw someone mention a wall outlet USB adapter but I can't see myself using any such thing. I'd rather plug a laptop or desktop in and use it as my hub. In that scenario, this cable is perfect for me as I don't have to worry as much about filling available wall outlets, and my USB hub takes up far less space in my laptop bag than a power strip would.