High performance: Smart USB Doorbell has ultra-low power consumption, long service life, and a working temperature range of - 20℃-70 ℃, which can withstand various adverse weather conditions. Modern and Practical Design: Our Wireless Doorbell has a fashionable appearance and practical functions. and sensitive, it can be remotely controlled, providing you with quick instructions to that you hear and open the a timely manner. Easy to Install: The Mini Door Bell is easy to install and can be installed in just a few minutes. Precautions: In environments with high wireless interference, the transmission distance of the Wireless Doorbell Receiver may be reduced. If no music sounds, check whether the horn wiring is disconnected. Colour:Black & White Material:plastic Package Contents: 1 x Doorbell 1 x Remote Control 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.