FeaturesDiscrete design to blend into your environmentEmits a loud 120dB alert and 4 different melodiesWiFi connectivity up to 20mSimple and easy to set up with two button pressesCompatible with iOS 8 or later / Android 4.1 or laterThe Link2Home Bell Chime simply plugs into any USB power supply and connects to your Link2Home doorbell over Wi-Fi through the Link2Home Pro app. It means you do not need to be near your doorbell or smart device when someone rings the doorbell.