I never thought of this before, A really unique mod.
I like the idea of this "modules for specific products" Idea. Would it be possible to make productivity modules for things that cant normally accept them?

Either way i'd like to see more things like this, makes me very interested

I don't see the purpose of this mod. The inserter module is very expensive, and you could do the same thing with a speed module and productivity module for less resources, and they work on many more products :/

I have to agree.
Insane specificity like this is a fun idea, but it needs a point.
This is a productivity module that only works on inserters? What's the point? What makes it enticing, what makes me want to make it, as opposed to an ordinary productivity module? What sets using these modules apart from productivity modules?

I get if you were to make everything require specificity like this (although that would probably be on the excessive side), but on its own, it's currently missing that key purpose.

I'm interested to see where you take this, as this is completely untapped design space.

Yeah, I have to agree on what BlooSkies said too. If it would make more Plates out of ore or something I would see the point. But inserters? It's not like you use vast quantities of them. The idea has a certain flair to it though.

Why did I make this mod in the first place? I made this mod mainly to expand my programming skills and, as NoOneIsHome and BlooSkies pointed out, make a completely original and new idea out of the resources the game has available.

I do in fact realize that this module needs more power and should cost fewer resources to make, and I plan to balance these better in a future update.

As Xelan pointed out, inserters are not used in vast quantities, but they are an essential part of any factory--putting things in machines, taking things out of chests, loading and unloading chests, etc. Inserters are also used for science.

Did you consider reduced material costs as a possible concept for these specialised modules? Would make them potentially more interesting, since lower production costs are always a good thing an belt capacity is the first thing that limits your production lines if you don't build in extra supply lines in the first place.

Xelan: I did change the costs slightly in the new 1.0.1 version, but right now I'm satisfied with the way they are. I wanted to use the vanilla modules as a template for my new ones, but I wanted them to be slightly easier to make due to the fact that they are less useful. To balance this, I increased the productivity of these modules so it is possible with 4 Tier 3 modules in a Tier 3 assembler to get 52% productivity.

I didn't want to make the modules too easy to build because they could be overpowered.
I have contemplated the possibility of having something like an "Inserter Circuit" that is put into Inserter Modules, but I wanted to stay a bit closer to the template provided by the vanilla modules.