Meanwhile, TSA: no water bottle for you. Bring a cell phone, laptop battery, and a spare 20,000 mAh backup battery (of dodgy provenance no less)? Sure no problem.
Loved this when I was vaping and would travel for work.
Give me a ton of shit over my variety of juices, in 30mL bottles in my 3-1-1 bag...but the half dozen loose 18650s? Not a problem.
(They weren't totally loose, I had silicone sleeves on them and would rewrap them if they showed a little wear on the wrapper. I used mechs and RDAs, I wrote the newbie guide to rebuilding on reddit...I was pretty safe about it).