Rigid Shielded 2-Card Polycarbonate Holder protects 13.56MHz RFID technology smart cards including MIFARE, iClass, PIV, CAC, TWIC and FRAC cards. These card holders block 13.56 MHz which is HF, they are not designed to block UFH. 

Thumb notches for easy card removal.  Made in the USA.  Meets BAA (Buy America) and TAA (Trade Agreement Acts).  Slot Pull Strength: 89lbs.  50 per package. Priced per package.