Post Office Box and Post Office Box System

A post office box comprising an enclosure bounded by a front face, a rear face, and side faces joining said front and rear faces,

• said front face having a front opening fitted with a closure device comprising at least one first closure element that can be moved between an open position in which the interior of said enclosure is accessible through said front opening, and a closed position in which said front opening is able to be closed by said closure device;
• and
• said rear face having a rear opening and
• comprising a fastening device able to keep said first closure element in said closed position;
• wherein a securing element mounted movably close to said rear face is connected to said first closure element by a connection designed to transmit to said securing element a movement proportional to the movement of said first closure element;
• and wherein said fastening device is mounted close to said rear face and comprises an electrically controlled movable member designed to engage with said securing element when said first closure element is in said closed position.