3D printers can make solid objects with internal structures.
It’s the same basic idea as an envelope, as in you need to open it to see what’s inside. However, opening it up inherently breaks the object so if you have it unbroken then it’s obvious that nobody has done so. XRay’s being an obvious risk.
It’s the same basic idea as an envelope, as in you need to open it to see what’s inside. However, opening it up inherently breaks the object so if you have it unbroken then it’s obvious that nobody has done so. XRay’s being an obvious risk.