The Sailor Moon store released a beautiful "Crystal Dome Keychain" during late December 2019. It shows the Moon Castle within the Crystal, and the bottom is inspired by Princess Serenity's dress. The price for the keychain is 2,500 yen (tax not included). It will also be available for sale via the Pretty Guardians Fan Club website. Please note that this is only for the Japanese fan club site, and not for the overseas members. Please click here to learn about using proxy service to buy from Japan.