Tiling Laser, Accuracy +/-1/4 in @ 20 ft, Battery Type AA, Features Dual Leveling Vials for Use on Vertical Surfaces, Establish Angles With the Built-In Protractor, Laser Beams Project Over Wet Mastic or Concrete, Perpendicular Lasers Form a 90 Degrees Reference for Floor Installation, Ruled Ends - Inch, Metric and Angle, Includes (2) AA Batteries, Number of Beams 2, Number of Planes 0, Number of Dots 0, Number of Lines 2, Working Range with Detector - Maximum Not Applicable