You don't need to run wires or install an elaborate system in order to receive an immediate alert if motion is detected inside or near your home. The Household Motion Alert System is designed to monitor movement around your house, notifying you instantly if motion is detected via audible and visual indicators. Best of all, the Household Motion Alert System is easy to set up, with the sensor alerting the receiver wirelessly. The motion sensor requires a 9-volt alkaline battery, sold separately.Mount the motion sensor indoors or outdoors, anywhere you fear security may be breached. With its range of 300 feet, you'll be able to place the receiver in any convenient location in your home. If you need to cover a distance further than 300 feet, use the Household Alert Wireless Repeater to extend the communication range between the Skylink wireless devices and ensure the security of your home. The included receiver will control up to four different sensors. Sold separately, you can add a Household Garage Door Alert Sensor or a Household Door/Window Alert Sensor for security, or a Household Water Alert Sensor for water leaks. Additional motion sensors are also available. If you're planning to add a garage door sensor to receive notification should you leave this door open, you can save by purchasing the Household Alert Combination Set. When multiple sensors are installed, only the corresponding zone LED will flash, so there will be no confusion. In addition, you'll know which zone is being triggered by the number of beeps emitted in succession. If you're planning to be working in an area that normally triggers your motion sensor, the audible alert can be muted easily.