This is Official microUSB Power Supply Unit from Raspberry Pi Foundation !

The official and recommended universal micro USB power supply for Raspberry Pi. We’ve tested this supply in all kinds of situations, and it’s as solid as a rock; it’ll keep feeding your Pi the steady 2.5A it needs for proper performance.

There are also four interchangeable mains adaptors — you can use it in the UK, Europe, Australia and the United States.

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