PURPOSE: To eliminate loss of information stored in a magnetic memory means by a method wherein a permanent magnet is installed in a pan-shaped ferromagnetic vessel with some gap provided between the magnet and the vessel and the upper surface or attracting surface of the magnet is abutted against by a disk- shaped ferromagnetic shield to reduce the leak of magnetic field.

CONSTITUTION: A ferromagnetic sheet 2 is fixed to the lower surface of a cylindrical permanent magnet 1 and its edge is bent up for the formation of a rising edge 2a along the side of the magnet with a gap 3 between the side of the magnet 1 and the rising edge 2a. The upper surface or the attracting surface of the magnet 1 is provided with a disk-shaped ferromagnetic shield, with its diameter roughly equal to that of the magnet 1, fixed thereto with an adhesive agent or non-magnetic screws, with the gap 3 around the magnet 1 left open. This prevents the leak magnetic field from spreading, and a handbag using this metal does not cause an erasure of information stored in a magnetic card. The gap 3 may be covered with a removable ferromagnetic sheet if necessary.