PURPOSE: To omit a direction detecting device in an external processing device by making a shape of a card containing a storage medium asymmetrical so that it cannot be inserted into a card inserting port except its regular direction.

CONSTITUTION: A card having a magnetic stripe 1 as a storage medium is provided with, for instance, an inclined surface 3 and 2, and is asymmetrical. Also, the card is inserted from a surface 4 to the card inserting port 5 of a device. As this card is inserted into the inside, a movable part 6 slides toward the right, and when the insertion is completed, the movable part 6 returns to the original position by a spring 7. The surface of the card, which is conformed to this inserting port 5 is only the surface 4, and accordingly, it cannot be inserted except the regular inserting direction.