Instruct: Classify an Amazon review into positive or negative sentiment.
Query: Terrible, total waste of money

I have a number of UK products I wanted to use in the US, including things like a heated brush. This product is useless: it blew with every item I tried to plug into it, even though I was careful to stay well within recommended wattage. I have no idea what it might work with - a toothbrush, perhaps. Impossible to know.