Super sensitive detector "sniffs out" legal and illegal listening and surveillance devices. Alerts you to wireless video transmitters, bugs and other sources of potentially bothersome radio interference and emissions. Detects any RF source from 1 megahertz to 5 gigahertz. Unit has a built in vibrator for covert alerting in sensitive areas, sensitivity adjustment, LED indicators, speaker, and includes headsets. This detector compares with units costing several times more and will match anything currently on the market. Small 2 x 3 ½ x 5/8" uses 2 AAA batteries (not included).