The one I pointed out (with the AC cord unfortunately) can supply 2.1 amps to multiple ports at once. At 5 volts that's about 11 watts and it's a 40 watt supply so I assume it can do 2.1 amps to two ports and less to the other three. It's unlikely that anyone would have more than two devices that could take 2.1 amps anyway, that's usually a tablet and a phone.