RFID is the abbreviation for radio-frequency identification. RFID has a frequency of 13.56Mhz. This frequency is used to receive data from Send credit cards, passports and public transport cards to the respective terminals. Our ACTIVE PROTECTION CARD has an integrated chip. This sends interference signals at exactly this frequency. As a result, the receiving device cannot receive correct data. This protection is guaranteed to work. Only one card is used for full protection.