8 TSA-Approved Items That Still Surprise Seasoned Travelers

7. Empty (Completely Dry) Reusable Water Bottles of Any Size

TSA doesn't limit the size of empty containers—only full ones. You can carry a gallon-sized hydration jug through security, as long as it's bone dry. This policy is gold for eco-conscious travelers and anyone who refuses to pay $6 for airport water. The key is ensuring it's truly empty; even residual droplets can trigger a bag check. Collapsible bottles are especially clutch, taking up minimal space when flat. Once you're past security, fill up at water fountains and stay hydrated without the markup. It's a small rebellion against airport pricing, and TSA fully sanctions it. Hydration activism at its finest.