This can be very handy when you need a Dremel tool but can't or don't want to get out the extension cord. Biggest drawback is that it Stalls way too easily and that trips the internal circuit breaker. Then you have to shut off the tool, wait a few seconds, then you can turn it back on. That means that a lot of simple quick jobs are going to take a lot longer than they should have. Only option is to be very very careful not to Stall the tool but then it will still take longer to finish the job. I'm not using this tool anywhere near what I had hoped to, instead I'm getting the extension cord out and using my regular Dremel. Other drawback is that the Battery Packs are very expensive considering their size and power. I would still buy it but overall I'm disappointed with this tool and will continue to look for an alternative that doesn't have this tool's problems.