A marker device for merchandise items has blanks of high magnetic coercivity material spaced along a strip of high magnetic permeability material. The strip and blanks are the same width, produced from three ribbons of material, one ribbon of the high coercivity material, another of the high permeability...http://www.google.fr/patents/US5602528?utm_source=gb-gplus-shareBrevet US5602528 - Theft detection marker and method
