Keep your info to yourself. The size of a credit card, Scanner Guard is a card that's designed to protect your personal information from would-be thieves. How? By employing built-in, special metal layers that prevent radio-frequency identification (RFID) scanners from reading and stealing data from your credit cards, debit cards, or driver's license. Place up to six credit cards between the two Scanner Guard cards for coverage. Not all cards contain RFID contactless technology - this product only helps protect cards with RFID contactless technology Includes four Scanner Guards; two sets of two Metal layers help block RFID scanners Place up to six credit cards between two Scanner Guard cards Measures 3-3/8"L x 2-1/8"W Imported