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Matching the gear to the task

Shop for Cordless Drill Drivers

A red car driving up a hill The gears in a cordless drill driver serve the same purpose as the ones in a car. Putting the cordless drill driver in a low gear means it will operate at a slower speed but it will deliver more torque (turning force). Putting the cordless drill driver in a higher gear means it will operate at a higher speed but will deliver less torque.
Gear selector switch viewed from above Select a higher gear when less torque is required (when working with softer materials or smaller screws).

Select a lower gear when more torque is required (when working with tough materials or larger screws, or when drilling.)

 Wonkee Donkee says "If you get confused think of a car you switch to a low gear to when you need more power (e.g. when going up hill) and a high gear when travelling at speed"