It is requested that this article, or a section of this article, be expanded. Please help the Harry Potter Wiki by expanding this article to give more complete coverage of its subject.
A Cuckoo clock is a Muggle device that shows the Common Cuckoo and sounds like a bird. The Dursley family owned one, and it was able to give one of the Letters from No One. It started going off in the Prisoner of Azkaban when one of Aunt Marge's buttons flew off and hit the door, making it go off repeatedly while Marge inflated.