Aluminum wallet with elastic back pocket ID credit card holder, RFID mini slim coin purse, automatic pop-up bank card box Main Material : Metallic Gender : Unisex Pattern Type : Solid Item Width : 6cm Item Length : 9cm Item Type : Card & ID Holders Use : Credit Card Item Weight : 65g Material Composition : Aluminum + Lycra + Plastic Closure Type : No Zipper Shape : Box Style : Casual Capacity : 2 ~ 6 banknotes, 4 ~ 8 credit cards Interior : Coin Pocket,Note Compartment,Card Holder 1. RFID lock. Limit the Ki N G frequency to 10 megahertz to 3000 megahertz, including 13.56 MHz for our credit, debit and ID cards. Be sure to avoid damage from the wallet and all rfid scanners and readers. Stay away from the troubles of our lightweight and reliable wallet to give you peace of mind when traveling, shopping and performing everyday tasks. 2. Use it every day to prevent the RFID card from passing through the wallet to avoid RFID reading.