Bests & Worsts Reviews from Amazon

As tested with a professional pentesting tool, these do not work to protect your NFC cards from being cloned. Sandwiching my NFC credit card between two of the blocking cards still offered no protection. Even after adding all four cards between the device and my credit card they were only able to partially block the signal from being captured--Obviously, that's not what they're designed for nor what they're advertised to do. Since blocking NFC is one of the critical features from the description, there's no possibility of giving this item any more than one star.