Mini Cryptex from The Da Vinci Code. Made of heavy, engraved, antiqued metal. Measures approximately 10 x 4.The Cryptex is a fictional device used by Dan Brown in his book The Da Vinci Code, where it is described as a sort of safe deposit box, used to hide a coded message. In Browns story, the characters attempt to access the secret of the Holy Grail by opening various Cryptexes, each contained within the other for the purpose of increasing security.