American flight security...

"“Maybe if you lit it on fire, he’d pay attention,” I said, risking arrest for making a joke at airport security. (Later, Schnei­er would carry two bottles labeled saline solution—24 ounces in total—through security. An officer asked him why he needed two bottles. “Two eyes,” he said. He was allowed to keep the bottles.)"

12oz Bottles of liquid labelled "Saline Solution" (for contact lenses) are allowed, other liquids over 3oz aren't allowed... link