An electronic storage device includes a first memory segment having at least one source block to store information, a second memory segment having at least one backup block corresponding to the source block to make a backup of the information in a LSB memory page of the source block and a control unit connecting with said first memory segment and second memory segment. The first and second doors each include a tumblehome portion that extends inboard of a first rotation axis and a second rotation axis respectively. A second memory stores the directional image. The electrons flow in the direction of an anode that absorbs their energy, generating electrical current in one direction, known in the electrical field as direct current.