The machines used thesedays are no longer “X-Ray” machines. They are not looking for metal items, they are thoroughly searching the contents of the bag and the scanners they use provide an absolutely incredible view of the contents of a bag.
So, yes, they can very vividly see whatever it is that you have inside that bag.
Travelling with sex toys is far from an unusual thing however. A TSA agent will see something like that go through the machine many, many times a day. They are, by and large, discrete professionals. If they see something in your bag that may be offensive and/or embarrassing, and if it so happens that they need to search the bag, they will ask you to go to a private room before they search your bag in the open.
Keep your toys in a small sealed bag within your luggage with no liquids or especially dense items (like books — the machines can’t see through them well, and they may elect to hand-search around them) around them that could provoke a search, and they won’t need to go probing into your personal items.
- Metal detectors, as their name implies, only detect metal.
- X-ray scanners, those they scan your bags with, will certainly detect presence of the sillicone object in question. Depending on the object and operator’s experience and training, he/she might or might not figure out what it is.
- Body x-ray scanners (e.g. backscatter x-ray scanner) will only “see” the silicone if it is on your person above skin. If you talk about sillicone implants, then no, they won’t be detected, because body x-ray scanners do not penetrate skin.
- Explosives Particles Detectors also will not detect sillicone, unless the object in question contains explosives, or, depending on the EPD machine, drugs.
- Liquid Explosive Detectors – same as above.