When it comes to TSA makeup, any product that is a liquid or gel-like consistency counts as a liquid. This includes foundations, concealers, primers, serums and even mascaras. The rule of thumb when packing liquids in your carry-on bag is that all containers must be 3.4 ounces (100ml) or less. Any products with this capacity are allowed on the plane but must fit into one quart-sized clear plastic bag for security check points. When travelling with these items they should also be placed in an easily accessible spot such as near the top of your bag so you can quickly pull out at security checkpoints. It's important to make sure all caps are tightly sealed and containers have no leaks before placing them into the quart sized bag - if not they may not be allowed through security!