A professional carpenter or installer can likely use a 12-volt tool all day long without needing an 18V tool. Thanks to lithium-ion technology, today's 12-volt drills and impact drivers perform a lot like yesterday's 18-volt tools. Some even seem to fall somewhere in between the two categories.

Pull the charger out of the socket once the battery is fully charged. A full charge will take around 60 minutes. Slide the battery into the holder on the drill until you hear the locking mechanism engage. As before, the switch for the direction of rotation must be in the intermediate/middle position.

Speed-range switch: High is for drilling; low is for driving screws. Look for the widest range between them. Forward/reverse switch: Should be easy to operate with your thumb and trigger finger. Hand grip: Texture and contour should aid your grip; try out the grip before you buy.