RFID Anti Theft Blocking Card Secure Protector Sleeves 5 Pack - Prevent Wallet Skimming RFID Sleeves protect credit and debit cards from identity theft-Makes your credit cards invisible to Hackers! Unconditionally 100% guaranteed to work or money back. See our other listing for larger quantities. Made of aluminum which protects all smart cards having a frequency of 13.56MHz Over 75,000 sold.High Feedback! Electronic Pickpocketers are everywhere...airports, cruise ships, coffee shops, etc