A key question is would a duplicate of this ring function to open the box?
If any duplicate would function (even if it had to be molecule position exact) to open the box then the ring is not part of the infrastructure,
it is simply a property of the infrastructure that it will open if a physical object of this description is applied to it.
If on the other hand it has to be this ring, then it is part of the infrastructure.
If it is thus not part of the infrastructure, then it would not show up to demons at all -- though if you wanted to make it obvious you could have it trigger Aetheric Resonance saying that a bit of Aether was stuck to the surface from the last time it had contact with the box.
If it is part of the infrastructure, then it would show up as infrastructure (which IIRC demons immediately know about). I would tell any demons detecting it as infrastructure that it is a component of the infrastructure, so they don't try and use the ring on its own.
You could break the infrastructure into two, one logistics and the other concealment as @Nyoze suggests. However I wouldn't, this kind of split definitely makes sense for bigger infrastructure (and I would encourage it), but for things so small it is a bit much work.
- Two pieces of infastructure means two linchpins. Means two vulnerabilities. Deciding what is a suitable linchpin for two things so small is hard.
- Second: You would have to have separate tasks for the logistic and concealment part, and if the box is just in the end a mundane box (not a portal to pocket realm or anything else) than that doesn't make sense.
If you hadn't already told the party that it was logistics infrastructure then saying the whole thing was concealment infrastructure would be valid. Though the line between concealment and logistics can be a bit blurred at times, so it doesn't matter really -- both are valid.
I would not try and think of it as a part of forming an occult matrix. Eg the notion that when the ring comes in contact with the box Output is produced in the form of the box which contains things. That kind of logic is much more prevalent in the mortal aimed God Machine Rules update than it is in the Demon rulebooks. I find it doesn't make too much sense except for infrastructure that is designed to be a big thing that happens as one-off, eg summoning an Angel, turning a meteor etc.