If it has an automatic leveling system, the device is able to level itself. It will project a horizontal and/or vertical reference line around your work area. Then, it will automatically find and maintain level within a specific range. Some of them will also have a bubble vial, so you can do some rough leveling before the device makes the final adjustments. Many of them will continue to level themselves if the setup or platform is accidentally jarred. And in many cases, they will shut themselves off if they get out of level by more than 3-5%.
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