Liquids and containers on a plane
Ordinary liquids at a US checkpoint
For a departure from the US, pack ordinary carry-on liquids, gels, creams and pastes in containers of 3.4 oz/100 ml or less. They must fit in one clear quart-sized bag. TSA assesses the container's capacity, so a 6 oz bottle with only a little product left is still too large for the ordinary rule. Sauces, jam and toothpaste need the same check.
Drinks and containers
Check a full bottle of coffee, juice or water against the rules at each checkpoint on your route. An empty reusable bottle can be filled after screening; check its contents again before another security check. A coffee thermos still contains a drink, and ice can melt on the way to the airport.
Medical and baby liquids
Medically necessary liquids and baby food or drinks can follow separate screening conditions. Tell the officer about larger amounts and present them for inspection. Read the medical travel guide or baby food and drinks guide before packing them. A dry powder is screened under its own rules.
Check what the liquid contains
Tattoo ink uses the ordinary carry-on container limit, while a larger permitted bottle may travel in checked baggage if sealed against leaks. Its formulation still matters: the liquid-size rule does not override a hazardous-material restriction. A snow globe contains liquid in glass; check its capacity and protect it from breaking. Alcoholic drinks have separate strength and packaging conditions. Check each part of a kit on its own.
Sources: TSA: travel tips and TSA: complete item list.