PoweredUSB

PoweredUSB, also known as Retail USB, USB PlusPower, USB +Power, and USB Power Plus.

It allows for higher-power devices to obtain power through their USB host instead of requiring an independent power supply or external AC adapter.

It is mostly used in point-of-sale equipment, such as receipt printers, touch monitors, and barcode readers.

 

There are different power shapes and color-coded versions of plugs:

• Grey/Yellow - 5V (7.5-30 W)

• Teal - 12V (18-72 W)

• Red - 24V (55.2-144 W)

• Violet (alternative) - 19V

• Red (alternative) - 25V

• Black - alternative for any voltages higher than 5 V

more info: https://en.wikipedia.org/wiki/PoweredUSB