The key is a silver Celestial Spirit Key, with the bow being designed similar to a cuckoo clock with the crest in the middle, colored brown. The blade of the key is of simple design, similar to other silver keys.
While in possession of the key, a Celestial Spirit Mage may be able to summon the Clock Horologium by reciting the quote, "Open Gate of the Clock! Horologium!". This summons Horologium, a walking grandfather's clock that is able to shield people inside its body.