Abstract: There is described a case for valuable documents, such as notably checks, credit cards, bank notes, etc., comprised of a box with a lid and a closure which may only be opened by inputting a code number, as well as a capsule or phial filled with a pressurized liquid which can destroy or make useless said documents, in which said capsule or phial is made completely or partly from fusible material, and said capsule or phial may be opened or unplugged electrically when electric or electronic means the case is fitted with, are operated due to any break-in attempt.