Paint armor helps to protect your car and reduce the paint damage from small stones and abrasions. It consists of a very strong, but thin plastic film that is applied over the paint. Tesla used to offer Paint Armor installed before or after the car purchase, but it is no longer available (as of September 2013).
Many custom installers also offer services to install paint armor.
On some car colors, such as white, the line where paint armor ends may be visible and may not be acceptable to you.