such an insulated beverage container. very common, right. you take off the top, pour your drink, drink and put this back on. roger, might what they are concerned about is -- actually i'm crack this open, which is the wall in between. >> right. >> now, this space when i calculated, it holtz about o-- holds about one cup of a liquid, about eight ounces. what might be able to be slipped inside a thermos like this inside this wall space? >> watch out for the explosive eggnog, number one. i think there is always a concern that if you have any type of container where a chemical explosive, petn, some of the things that have been used in the past, maybe even a peroxide-based explosive, although very unstable, that is what tsa would be looking for. there's also the possibility that terrorists in the past have used one container to put one chemical compound in and then brought another container, another compound in a separate item and combined them once they