Picked this up this week and it's really comfortable. I like steel generally as they are cleaner but I travel for work 4 or 5 days out of the month. I like itergrated locks as opposed to paddle locks. https://www.amazon.com/gp/product/B07FL25NT4/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 Another member posted a plastic lock and key https://m.dhgate.com/product/doctor-mona-lisa-plastic-concealed-lock-for/411487808.html#pd-018 So I think I'll be safely restrained and able to get through security.
You'll probably make it safely through metal detectors with that, especially if you use the plastic integrated lock. If you have to go through the body scanner, though, it's likely to flag your crotch. So you'll want to have a story or explanation pre-scripted in your mind as to what you're going to tell them when you get pulled aside and patted down as to what it is. Being honest with them is perfectly fine, of course - there's nothing illegal about wearing a chastity cage. You may get lucky and never need it, but I am by nature a planner, and I would always have something prepped ahead of time just in case.