The Skyscan model p5-3 Lightning detector is the newest high technology weather monitoring product available anywhere in the world. It is a hand-held instrument with an electronic system to detect the presence of Lightning/thunderstorm activity occurring within 40 Miles of your location. It uses patented technology (full digital microprocessor insuring accuracy and reliability) to determine the distance to the detected Stroke. The distances are indicated in four ranges: 0-3 Miles (0-5 km), 3-8. Manufacturer Contact Information Not Applicable