This is a thwonger, otherwise known as a spring-style doorstop. It makes a loud thwong noise if you run into it. The builder chose these for the house and we have not replaced them yet.

But did you know that if you shut the teenage cat out of the bedroom at four in the morning because he is being a monster, he will quickly learn that he can reach under the door and thwong the thwonger until you let him in again? We know this now. (picture of cat for cat tax)
#Cats #Caturday #CatsOfMastodon