1,Electronic self-leveling, 2,wide leveling range, 3,high precision and stability Specifications:Laser wavelength: 635 ... class: Class IIAccuracy: ±1/4"/100 ft. (±1 mm/5m)Self-leveling range: ±3°Power: 3x AA alkaline batterySize: 10" x23 5 ... , two horizontal lines, up & down plumb beamSelf-leveling, and laser flashing when beyond self-leveling rangeSwitch-able between the continuous laser and the ...