The system allows users seeking to adopt to search based on the desired attributes of an animal and the availability of such animals. These electronic records, owned and controlled by the individual, may then be made accessible in selected parts over secured lines, to appropriate care providers, insurers and suppliers. The extension of the magnetic areas or the gap areas along the security element is preferably chosen so that the magnetic signals of adjacent magnetization steps interfere constructively with each other when transported past the magnetic sensor.