For the purposes of aviation security, concealer is considered a liquid by the TSA and almost all international aviation authorities. Whether it is a liquid, cream, or gel formula, it must comply with the "3-1-1" rule for carry-on luggage. This means your concealer container must be 3.4 ounces (100ml) or smaller and must be placed inside a single, quart-sized, clear plastic zip-top bag alongside your other toiletries. Even "stick" or "pot" concealers are often treated as "semi-solids" or pastes by security officers, who tend to apply the liquid rule to any product that is not a dry powder or a solid bar. If you are carrying a larger tube of concealer or a liquid foundation that exceeds the limit, it must be packed in your checked baggage. To save space in your liquids bag, many travelers opt for travel-sized versions or "palette" concealers that are more solid in texture, though any creamy product is subject to an officer's discretion during the screening process.