Set of 3 card protection sheets with skimming prevention function. RS9Z017J Skimming/Radio Wave Interference Prevention Sheet PERFECT GUARD II Quantity: Set of 3 Features: Skimming prevention function, prevents radio wave interference with IC cards [How to Use] Example: By placing it between your smartphone and an IC card, it blocks interference with the IC card and prevents reading errors. Example: By placing it with cash cards or credit cards and storing them in card pockets such as wallets, it prevents skimming. *Using two sheets, front and back, is effective.