Saves you from info-snatching electronic pickpockets, and from leaning against the gas pump and emptying your bank account. (The downside of Radio Frequency IDentification.) Called the “EMvelope,” it’s an 8-3/8″ x 3-1/2″ x .012″ thick trim-able electromagnetic sheet (think Faraday cage with a floating ground) that blocks radio frequencies up to 2.4GHz. Cut it to size and slip it in your wallet, or wherever, and protect the data on your credit cards, “fast-pay” devices, ID cards, EZ-Pass, or anything else with an embedded RFID chip, including the new U.S. passports.
Don’t take any chances. From my favorite catalog.