Shield & protect personal data with these RFID credit card covers. ideal to be used in any wallet or purse, when placed on top of a credit card they block illegal scans of RFID chips embedded in modern-day cards, shielding data & preventing identity theft. Furthermore, ` Card Guards` also prevent 2 contactless cards in the same wallet being billed simultaneously.RFID means Radio Frequency Identification. Personal & banking information is stored on RFID chips in passports & credit cards. Criminals can easily scan these chips from a distance, taking the information like a digital ‘pick-pocket’. This allows them to perform identity theft & other digital crimes.