A method for data storage of a memory unit and a memory unit using the same are provided in the present invention. Each cover includes an integral fracturable tab depending from one end and coacting means on the container for securing the tabs in a snap-fit relationship when the cover is positioned to close its respective compartments. Consequently, a thermal separation is achieved in the filling wedge between the feed channels and the wedge surfaces, which makes it possible to work with high operating temperatures for the capsule shell material. The guide plate is configured such that, whenever the guide plate is registered with the multi-well block, fluid communication is established between each well and an associated fluid passageway. The obfuscated messages are stored and access thereto is controlled by only permitting authorized users or applications to decrypt or access the message.