I've been having a lot of difficulty getting to my door lately. My two favorite dogbells have decided that they had the job for almost 14 years and they are too old for the job now. I can no longer use the excuse "I didn't hear you knocking". This wireless doorbell although small is loud enough for me to hear it wherever I am in my small apartment. It came as a plug and play unit. All I had to do was pull the tab from the doorbell, test the distance where to place the receiver, choose my prefered sound and once the distance is verified doorbell is ready. It's perfect for my need. I would definitely recommend.