DM S50L utilizes ultrasonic technology to measure up to 50' and with laser pattern to illuminate target area to aid accuracy. Measurement function includes length, area, volume, double segment, and continuous measurement. Converts between feet/inches and metric system. Double segment feature measures lengths up to 100'. Measures in feet and inches, also measures in meters and centimeters. Accurate to +/- 0.5%. Easy-to-read LCD screen. Great for estimating paint, wallpaper, tile carpet, and flooring. Uses (1) 9V battery (not included).