[Versatile Door Chime]The M8 Wireless Door Sensor Chime is perfect for welcoming customers and notifying staff of arrivals and departures [Customizable Melodies]Choose from 60 different music options to set the perfect tone for your business environment [Adjustable Volume]Features 5 levels of volume control, allowing you to set the ideal sound level for your space [Long-Range Connectivity]Boasts an impressive 300-meter straight-line range in open areas, ensuring reliable performance even in larger establishments [Easy Installation]Split sensor design with a compact door magnet and separate receiver for flexible and convenient setup Specifications: Product Model: M8 Music: 60 musics Volume: 5 levels Door magnet size:64mmx39mmx14.5mm Receiver size: 56mmx56mmx20mm Door magnet sensor battery: 12V 23A battery (included) Receiver: plug-in use (AC 100-240V) Remote control distance: 300 meters in a straight line on the open ground (data from the factory laboratory) Material: ABS