USB bus powered, no need for an AC adapter.

USB自身供电，不需要一个适配器。

youdao

The Medium Attachment Unit(MAU)is a pivotal circuit unit in bus powered Foundation Fieldbus devices. It is one of the most difficult problem in the hardware-design of FF devices.

媒体结合单元（MAU）是总线供电的现场总线仪表中的关键部件，也是硬件设计中的难点。

youdao

Ten or 20 years from now, the car you drive or the bus you ride may be powered by something other than gasoline.

10年或者20年之后，人们驾驶的车辆，或者搭乘的巴士，可能不再使用汽油。

youdao

If you travel by bus in Sao Paulo,Brazil these days your vehicle may be powered by hydrogen fuel cells.

VOA: special.2009.09.07

The G-RAID mini is FireWire bus powered - even when using USB 3.0 for data transfer.

ENGADGET: G-Technology updates G-Drive mini and G-Raid mini with 1TB HGST Travelstar hard drives

G-RAID mini can be FireWire bus powered.

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The two 5W-powered USB ports allow users to connect even two bus-powered external hard drives and also function as a backup battery for two iPads.

ENGADGET: Hyper debuts iUSBport mini, 2 and HD cloud storage and streaming devices (hands-on)