BLACK+DECKER BDL220S Laser Level 2-bubble Vial With Backlight For Increased Visibility 360deg Rotating Wall Attachment Projects Laser At Any Level Includes 2 Aa Batteries 360-degree rotating wall attachment projects a laser line at any angle Two extra large backlit bubble vials are provided for maximum accuracy and visibility Ideal for hanging pictures along a stairwell, hanging mirrors, installing curtain rods, and other domestic items This is a Class 3R laser product, Power output  5mW 2-year limited warranty