Effective Distance: Up to 328 feet (100 meters) working range between receiver and transmitter, allowing you to place it farther away from the receiver to warn your family, uninvited guests or lawyers or anyone visiting you home or business. Wireless Plug-In Receiver: Portable wireless plug-in receiver plugs into any standard socket. Sensor uses 3 AAA batteries (not included). The detection time delay between motion sensor alerts can be configured from 15 seconds to 30 seconds by simply placing the sensor at the driveway entrance and placing the receiver at home. APPLICATIONS: Perfect for front doors, window frames, driveways, sidewalks, and anywhere in your home you'd like to receive motion alerts. Its also good to remind business owners who work in the back or out of sight that customers are coming into their store. EASY INSTALLATION: For this visitor chime, no wiring, no installation trouble, the sensor can be mounted on the wall. You just put in the battery (not included) and place the wireless motion sensor and alarm receiver anywhere you like. Receiver button: 1. Music: 38 pieces of music are optional, the music logo button on the side can be adjusted 2. Volume: three-speed volume adjustment (high, medium, low) side volume logo button to adjust 3. Sound and silent can be set (sound: sound + indicator light silent: indicator light) Packing List: 1 X Receiver, 1 X Transmitter, 1 X Instruction Manual