a balloon or air container with something on the outside of it to make contact. barometric devices are difficult to detect unless you have a barometric detector going in, which this airport does for any cargo loaded in and baggage. each piece of baggage that goes in is pressure tested forebear row metric device. that does not and would not prevent anything on a timer or some other kind of approach as well, though. >> and bob, to this point, you heard pamela saying that if it was a device like that that had a pressure trigger, that intelligence officials -- u.s. intelligence officials believe that is very significant, that they do not believe isis would have had that kind of sophistication. you're saying you think they did and very easily. >> well, erin, they are wrong. in 2003, the cia raided a safe house in baghdad owned by a man who made these devices.