This tool is affordable and powerful, a fine item for the hobbyist or amateur user. It is not suitable for professional or high duty cycle use. The hand piece becomes very hot with extended continuous operation.The hand piece is a jacobs chuck but it is not high quality. It is not precise enough to chuck drill bits finer than about #50 and anything larger than that up to roughly 1/8" is fiddly to get properly aligned. A great improvement would be an optional variable size collet chuck similar to Dremel tool for these fine sizes. Anyone buying this with an eye to drilling fine holes would do well to look around for an adapter that could be fitted to the jacobs chuck to do that.Otherwise, the tool represents a good value.