Cordless pistol-grip drills position the user's hand behind the bit-holding chuck to keep the tool steady and control the amount of pressure applied to the bit during drilling and driving. They provide ergonomic handling in a range of positions on vertical and horizontal surfaces. The pistol grip has a trigger switch that is pressed to activate the drill. Cordless tools run on batteries, so they are more portable than corded drills and allow use where a wired power source is unavailable. They use brand-specific batteries, which fit different tools of the same brand that have the same voltage and use the same battery series.