Instruct: Classify the given review into positive or negative sentiment.
Query: Piece of crap

I purchased this product as a backup power source for my iPod, since I travel frequently and don't always have a chance to recharge. I tried it yesterday for the first time on a flight back to Boston from Frankfurt. I used the batteries that came with the TuneJuice and got no more than around 10 minutes of additional additional play time (it's supposed to give 14 hours of audio playtime). Thinking that the supplied batteries might have been old, I replaced them with four new batteries only to find them completely drained in around 10 minutes as well. So not only did I waste the money I spent on this crappy power source, I also wasted four more perfectly good batteries as well (not to mention the inconvenience of 6 hours of flight time without access to my iPod). My recommendation - buy something else.