There are a bunch of Simulation missions related to the AIC Factory that you can take on in Arknights Endfield. These missions help you understand the game mechanics while also helping you unlock system blueprints.
The Fitting Unit quest can be a bit complicated, even with the game instructions because they throw so much as you at once. I’ll show you exactly how to do all the objectives – including the bonus goal. Let’s get into it!
Fitting Unit Quest Guide
The Fitting Unit quest basically helps you understand how the fitting unit works. I recommend you pay attention because you will need to do this in some main missions – which can be quite confusing.
For example, you’ll be using the Fitting Unit to produce amethyst components in the Paving The Way quest later on.
Use The Fitting Unit To Produce Amethyst Parts
Starting off, after you’ve interacted with all the machines and gone through the instructions, you need to place the Fitting Unit. I recommend that you place this as close to the Automation Core as possible.
This is because you need to place down a transport belt from the PAC output port to the Refining Unit input port. Having it close by will make it much easier.
Once the connection is established, you can watch Amethyst Ores be transported to the Refining Unit.
The next step is to connect the Refining Unit output port with the Fitting Unit input port. This will allow Amethyst Ore to be converted into Amethyst Fibers. After that, you can watch the Amethyst Parts be produced automatically.
Repair The Zipline Tower With Amethyst Parts
Now that you have Amethyst Parts, it’s time to use them to repair the zipline tower. Start by interacting with the Fitting Unit output port.
Here, you will be able to claim the Amethyst Fibers and put them into your Backpack. Make sure that you have at least x5 Amethyst Fibers.

Next, go to the Zipline Tower and interact with it.

After that, select the Repair option to use the Amethyst Fibers. Doing so will repair the tower.
Technically, you can now complete the simulation. But there is also a bonus goal that you can easily complete as well.

Bonus Goal – Store More Amethyst Parts In The Depot
The bonus goal is a bit confusing because there are not many instructions that explain what to do.
In essence, what you need to do is connect the Fitting Unit output port with the PAC input port – using a transport belt as you’ve previously done. You are basically storing the extra Amethyst Fibers back into the Depot.
Once that’s done, you can watch the parts go into the Depot and the objective will slowly complete. Since you need to store x50 Amethyst Parts, this will take a while. So, you can just leave it running until the objective completes.
And with that, you can conclude the quest and get all the rewards!
Final Thoughts
That’s everything you need to know about completing the Fitting Unit quest in Arknights Endfield. Complicated at first but it does make sense once you look at it step by step. As you experience more of the game, you’ll have a better understanding of how the factory works. Be sure to complete the bonus goal as well to get all the rewards – it’s worth it even if it takes some time.
If you’d like to have the best experience without spending money, check out our free to play guide!

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