Advanced Infrared Induction: Utilizes the latest infrared technology to accurately detect movements, enhancing your security and convenience. Versatile Melody Selection: Features built-in songs, allowing you to customize the chime according to your preference or occasion. Wireless Connectivity: Easy to install with no wiring required, suitable for all types of residential and commercial . Motion Detector: Efficiently senses any motion within its range, promptly alerting you with your chosen voice message or song. Ideal for Use in Locations: Perfect for homes, offices, and stores, this doorbell enhances security and welcomes visitors with charm. Induction angle virtual: left and right 110, up and down 60 Sensing distance: 2-7 meters (depending on temperature changes) Sensor power supply : Battery type: Three seven cell batteries (not included in shipment) or power cord supply Volume level: Three levels of volume Music selection: 19 songs (welcome message 10/prompt message 7/emergency message 2) Due to different batches, there may be differences in product appearance and printed text, which will not affect use Colour:Black Material:ABS Package Contents: 1x Induction Doorbell Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.