sentences:  USB 3.0 supplies 5 V at up to 0.9 A (4.5 W) whereas hosts conformant to the USB Battery Charging Specification can deliver up to 1.5 A (7.5 W).As each PoweredUSB plug provides one of three voltages, the plugs come keyed in three versions, so that they will only accept connections from devices requiring that version's voltage.The connectors can be color-coded for different voltages