In 2023 (and remaining true in 2026), you can bring the electronic components of a dab pen or vape on a plane, but the contents are where the legal trouble starts. Per TSA and FAA regulations, all electronic smoking devices and lithium batteries MUST be in your carry-on bag; they are strictly prohibited from checked luggage due to fire risks. While the TSA’s primary focus is on security (bombs and weapons), they are not looking for drugs unless they are "obvious." However, because marijuana remains federally illegal in the U.S., if a TSA officer discovers a dab pen containing THC oil, they are legally required to refer the matter to local law enforcement, even if you are in a "legal" state. For international travel, the risk is extreme: countries like Singapore, Thailand, or the UAE have zero-tolerance policies where even a trace amount of THC in a dab pen can result in years of imprisonment or heavy fines. If you must travel with a pen, ensure it is completely clean and empty of any controlled substances to avoid a high-fidelity legal disaster.