Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Very poor

These batteries give out very quickly, and do not hold power. After a while, they will not even charge. This is not a reliable way to operate a tool. It is just too expensive to keep buying new batteries. The batteries are also quite heavy. I am back to using a chord: it is much better, and far cheaper. If I have no power, I will use a hand-cranked drill as a stop-gap measure: works fine.