We can never say it enough: make sure there is nothing in your carry-on bags that is on the Transportation Security Administration’s list of prohibited items.

On Monday, Federal Security Director Karen Keys-Turner and spokesperson Lisa Farbstein held a press conference on Pittsburgh International Airport’s Ticketing level to reinforce that message for travelers.

Two full-size tables completely covered with various liquids and gels seized in just three days at PIT—each of which caused minor delays at the security checkpoint when discovered—served as a vivid illustration of their message.

To learn more, watch this video.