The 4V Battery Powered 5-Speed Rotary Tool is the best cordless rotary tool on the market. This rotary grinder has a keyless chuck design with a variety of speeds to choose from so you can match power to your specific task. The dedicated on/off switch provides increased user control and the enhanced portability offers extra convenience. The increased comfort grip will help you work for hours without tiring your hands out while the tool free bit change makes it easier than ever to get back to grinding! We’re not sure how you ever lived without a battery powered rotary tool but now is the time to make the switch. If you call yourself a hobbyist do it with HART. New condition.