Made Of PET Outer Material With Aluminum Inner | Adheres To Back Of Your Phone With Strong Adhesive | Place Your Credit Card In Holder To Prevent Cyber Hackers From Stealing Your Identity | Prevents Data Transfer Between The Wallet And Reader | Works With Any Contactless Chip Card. Cards That Are Swiped Do Not Send RFID Signals And Will Not Be Protected By An RFID Blocker. Approximate Size: 2 1/2″ W x 3 5/8″ H, Imprint Area: 1 1/4″ W x 2 1/4″ H