This is a door knocker. You use it to knock on doors because it is very loud and you can hear it anywhere in the house. If you knock with your fist its very hard to hear. If you are the deliver man please use the door knocker as I am waiting for some very important documents that I need ASAP. I really don’t appreciate the attempted drop off while I was in the kitchen pouring my bowl of Cheerios without even a decent attempt at a knock.