52 Songs, 4 Volume Levels: This wireless doorbell has 52 melodic ringtones from around the world, which can be changed by pressing a button. This product has four adjustable volume levels (including silent mode), and also has a blue flash, the silent mode flash always lights up to meet your different needs. 400 Meters Range: The wireless signal can be transmitted in a very large range of 400 meters (in the open area), and at the same time the signal's ability to penetrate the wall is good, the signal can completely cover your home without interference from other devices. Memory Function: This wireless doorbell automatically saves the ringtone and volume you set, and automatically restarts after an accidental power outage or after being unplugged and turned on again, without you needing to reset it to your preferences. Waterproof and Dustproof: With IP44 waterproof and dustproof function, it can guarantee The wireless doorbell can normally be used outdoors. The working temperature is from -35C to 65C, which can withstand bad weather, high quality and low power consumption. Very Easy to Install: The signal receiver comes with a plug that can be plugged in and powered on, as well as double-sided tape and screws to fix the transmitter (button) wherever you want.