Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unsure

I bought two of these. I still can't get one of them to format and have no clue or instructions on how to return it. As for the other one it will only work in certain devices and not at all in my phone. The adaptors they come with don't work, so I can't use it in my computer at all. Definitely would not purchase online again.