Connects to your doorbell and alerts you when someone presses the button. Become aware when someone is at your door. When a visitor presses the doorbell button, the Medallion™ Series Doorbell Transmitter broadcasts a signal to any Medallion™ Series Receiver. Wired to your existing doorbell, it is activated by the same current that operates the doorbell chime when someone pushes the button. Easy to install and powered by the doorbell’s electrical circuit, there are no batteries to replace.