The opted rctd-20u wireless annunciator system is a wireless detection and alarm system that can transmit signals up to 2,000 feet. This system is the most effective perimeter alert system available and is ideal for your home and is commonly used for protecting businesses. It acts as a driveway alarm to inform you of approaching vehicles, a wireless doorbell, a warehouse delivery notification system and several other applications that makes it a complete security solution. Three different tone alerts to inform you of a security breach five different sensitivity levels incorporates up to 12 transmitters multiple detection patterns to ensure perfect aiming trigger system utilizes a weather-proof motion detection sensor the size of a softball (easily mounted on most outside surfaces) no wiring of any kind is required operates off a 9v battery that lasts two years (on average).

On-off control. Adjustable volume. Extra long transmission range of up to 2000 feet. Indoor and outdoor use. Easy installation and setup.