The Kingdom Hearts Key Rings are a set of officially licensed keychains released in 2010 by Square-Enix. In series 1, the keychains are each about 0.6 inches long, while in series 2 and 3 each of the keychains is about 4 inches long. The keychains are extremely detailed and based off of symbols that appear in Kingdom Hearts for series 1, while in series 2 and 3 they are based off of the Keyblades used in the Kingdom Hearts series.