Detects wood/metal studs through multiple wall thicknesses (1/2", 1", 1-1/2") Continuous live wire detection for safety LCD screen is back-lit for greater visibility when detecting studs Laser line can be projected along the entire length of the stud Versatile 2-laser set can be used separately or together to create horizontal and vertical laser cross lines Projects laser lines up to 20 feet onto a work surface Unique adhesive dots used to mount the laser module to most walls for hands free operation 8 Adhesive dots included Required Battery - 9 Volt and 2 AAA (not included)