1 .Five beam laser level 2. Easy to use, one people can handle it. 3. Accuracy: +-1/4"/100 ft. (+-1.0 mm/5m) Five highly focused self-leveling laser beams provide accuracy of 3/8"-in at 100 feet. Tough on the jobsite. Resists water, dirt and dust (IP54) Use to: Plumb and Align: Walls, Doors, Frames, Stud Beams, Windows and Skylights; Level Electrical Outlets; Stud and Curtain Wall Plumbing, HVAC, ...