With the Byron B432E, you can hear someone ringing the doorbell from up to 75 meters in and around the house. The package consists of a doorbell button, wireless receiver, and extra receiver. Plug the wireless receiver into a socket of your choice. You can take the extra wireless receiver to any place in the house. Useful for rooms where you normally don't hear the bell, such as the attic and the store room. Put your name on the backlit button, so your visitors know they're at the right door.