 The Nexus Century and Fast credentials are about the size and shape of a credit card. Inside embedded are a UHF chip and antenna technology similar to the EasyPass toll booth type technology where the person who owns a card would flash it as they approach the immigration point as they cross the border. A number is transmitted ahead of your car so that when you arrive at the immigration point your information has already been brought up onto a screen. So the immigration officer has you, your card and your photograph that's laser engraved on the card and of course now from the number that was transmitted from your chip and pulled out of a database your face on a screen as well so there's a three way connection that the immigration officer can make.