Okay, we have to start with the obvious, but let’s make it quick. Liquids over 3.4 ounces (100ml) are the boss of the carry-on rules. That fancy shampoo bottle? Into the checked bag it goes.
Then there are sharp objects. Your trusty pocket knife, that vintage straight razor, or even a sturdy box cutter are all no-go. The logic is simple: no one wants a surprise air-guitar solo with a sharp edge.
And obviously, firearms and explosives are a hard pass. You knew that. But what about the stuff that makes you raise an eyebrow?