Can A/C adapters with same 5.0V output but 850mA and 550mA be used interchangeably?

The 850mA adapter came with a Motorola mobile phone and the 550mA adapter with a bluetooth headset.

Thanks in advance for any help.
Answer: The 550mA one might work in the phone but will probably charge it slower. Putting the higher current one (850mA) into the BT headset, if it fits, might damage it.

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