DETECTING DISTANCE: Wireless Camera: 1 2GHz - about 20ft 2 4GHz - about 5ft, Cellular Phone: about 20 ft, APPLICATIONS: Hospitals medical centers or intensive care units where cellular usage is forbidden, Offices factories cinemas theaters concerts museums or art galleries that prevent video body bugs, Military or government premises that cellular or camera recording is forbidden, Offices restaurants or any commercial premises that would like to shun away cellular or RF disturbance, Find best signal spot for wireless CCTV Detect peeping camera in shopping mall toilet school toilet locker room and fitting booth club house hotel etc, SPECIFICATIONS: Size: L 87 x W 55 x T 24mm Weight: about 85g (including battery) Power: 3V DC (AAA/UM-4 battery x2) Detecting frequency: 50MHz - 3 0GHz Warning mode 1: Sound and 3 LEDs display Warning mode 2: Vibration and 3 LEDs display Warning mode 3: Silent 3 LEDs display and earphone output Sensitivity Tuner: Eliminate the environment interference (noise) SKU: KJB201