Electric screwdrivers are neat because they combine batteries, motors, gears and a switch into one extremely compact and powerful package. Let's take one apart and see what's inside! Here's the screwdriver we will be dissecting:

When you take off the cover you find all of the basic parts of the screwdriver lined up from one end to the other. You will find:

• A rechargeable battery
• A switch
• An electric motor
• A dual planetary gear system (cool!)
• A simple locking mechanism for the chuck
• The chuck itself, which holds the screwdriver

Ridges on the inside of the­ case and two long pins hold all these parts together.

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­­The parts inside are pretty simple. We'll look at the switch and how it sends electricity to the motor in the next section.

Tips for Tools Discovery Channel's Toolbelt Diva has tips and tricks you can use for home improvement and repair -- even if you've never picked up a screwdriver.

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