Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unacceptable battery life & will not hold a charge....

The original battery and the replacement battery is at best for light use... I charged the batteries and at most they would run is 15-20 mn and the battery will never hold a charge overnight [and that's NOT connected to the Multipro], so you have to leave it on the charger continuously if you need the Dremel at a moments notice.Should have gotten a regular plug in Dremel. The portability of the Multipro is nice, but not at the cost of crappy battery.