KJB Security OMNIDIRECTIONAL SPEAKER FOR DNG2300

• Listening with the help of a wall stethoscope placed behind the construction adjacent to cavity (typically from a top floor behindthe drop ceiling)
• Leakage of sound outside the target room through the void/cavities (for example, through the ventilation or common holes for the pipes of heating system)
• Bringing a wired microphone to a void or cavity
• Hiding a covert surveillance device in a void or cavity
• 1 x SP2300 speaker per every 100 feet