Product details:

Accurate within 1/8-inch over 50 feet, the DeWalt DW082K Laser Plumb Bob provides fast, self-leveling performance to save you time and frustration and help you deliver precise results. There's no knobs to adjust and no vials to keep track of, plus high winds never make it tough to ensure level performance. With two beams, projected plumb up and plumb down, this unit is incredibly simple to operate. Simply set it down, press the on/off button, and the well-focbeams settle in seconds, delivering small, bright dots that can be to make precision marks even in bright light conditions. A cross-hair beam pattern ensures that finding the center of the beam doesn't involve any guesswork, and sensor lets you know if the tool has been jostled or positioned outside its self leveling range, preventing costly errors. This kit also includes four AA batteries and a durable kit box to protect your laser during transport and storage.