Why spend hundreds of dollars on an expensive security system when an ordinary telephone can keep an eye on your home for free? The TeleSpy Motion Detecting Phone provides free, monitored intrusion detection 24 hours a day by combining a standard telephone with a motion sensor and a microphone. If someone enters your home, the phone will call you at any number you specify and allow you to listen in for 30 seconds, ample time to determine if the intruder is a friend or foe. Set the TeleSpy to dial your cell phone or your office, wherever you might be.Simply enter any telephone number you choose and turn the motion sensor switch to "on." Should an intruder be detected, the TeleSpy will call you instantly, and you'll be able to listen in via the amplified microphone. The listening period is about 30 seconds, then the TeleSpy disconnects and instantly re-arms to detect again and again. The integrated passive infrared sensor detects changes in the room's heat due to occupant motion. The range is in excess of 30 feet at which point the width is about 20 feet, creating a 45-degree wedge beyond the sensor origin. The hidden condenser microphone is strategically placed for maximum efficiency. It is amplified to insure that the slightest of sounds are heard, producing a high-quality listening experience. Additional features include adjustable handset and ringer volume.