How to get the Probably Stolen Module Bay Expansion Kit, raise a machine bay from 26 to 35 cells, and use Basic and Advanced Module Extractors.
Probably Stolen Module Bay Expansion Kit and Extractor
A machine's module bay is a grid, and a grid can be too small. The Module Bay Expansion Kit adds usable cells; the Module Extractor removes a module so you can move it to another machine. Together they are the hardware side of the module system, and both are harder to find than the modules themselves.
This page covers the bay stages, the kit's sources, and the two extractor tiers. For the module effects, see the module list and stats.
Bay stages and cell counts
The standard machine bay is 7 × 5, or 35 cells. It does not start fully open:
| Stage | Usable cells | Blocked cells | Notes |
|---|---|---|---|
| Initial | 26 | 9 | Corners and centre cross blocked |
| Stage 2 | 31 | 4 | One expansion |
| Stage 3 | 35 | 0 | Two expansions |
The blocked shape matters because modules have footprints. A 2 × 2 module needs a 2 × 2 free area. Even if the bay has enough total cells, the shape may not fit until you expand.
Each expansion is reported to add 100 credits to the machine's value. That is a small buyout benefit; the real reason to expand is fitting better modules.
How to get the expansion kit
The kit is not a standard vendor item. Community testing reports these sources:
| Source | Chance / amount | Notes |
|---|---|---|
| Dr. Jackson | 20% per restock | Also extra rolls on Day 20 and Day 40 |
| Monday Special Stock | 2 kits | Limited weekly stock |
| Serpico | Choice of 4 kits | Reward option |
Dr. Jackson is the most reliable long-term source, but 20% per restock means you cannot count on a kit appearing when you need one. Check the Monday stock and keep the Serpico reward in mind before spending it on something else.
If you see a kit and can afford it, buy it. The opportunity cost of waiting is usually higher than the credit cost, especially once you own a 2 × 2 module.
A Neural Core or a Corrupted Module can sit in storage for days if the bay cannot fit it. The kit is the enabler.
Which machine should get the first expansion?
Expand the machine that has the highest-value module waiting, not the machine you use most.
| Situation | First expansion |
|---|---|
| Chemistry finisher with a Quality module waiting | Chem Finisher |
| Hydroponic system with a 2 × 2 Quality module | Hydroponic System |
| 3D Printer with a full bay | 3D Printer only if the printer is a bottleneck |
| Machine with only 1 × 1 modules | Delay; the initial 26 cells may be enough |
A 2 × 2 module in a 26-cell bay can be impossible to place even if 26 cells are free, because the blocked corners and cross cut into the available rectangle. That is the main reason players think the bay is bugged.
The Basic Module Extractor
The Basic Module Extractor removes an installed module. It has six uses and costs 100 credits. Community sources report it can be bought from:
- The Retired Chemist
- A Supplier
- A Supply Runner
- A Scavenger
- A Revolution Raider
It can also be found in the Dumping Ground at a reported 0.3% search chance, or in a Foundry crate with a 25% chance of up to two extractors.
Six uses sounds like a lot until you start moving modules between machines. Track the remaining charges. A basic extractor with one use left is not a spare; it is a single decision.
The Advanced Module Extractor
The Advanced Module Extractor is reusable, with no charge limit. It costs 350 credits and is sold by:
- The Rare Merchant
- A Revolution Raider
- Dr. Jackson (reported 4% chance)
- Monday Special Stock
- Foundry crates (reported 12% chance)
The advanced extractor is the better long-term purchase if you plan to reconfigure machines. It also protects expensive modules: a Neural Core stuck in the wrong machine is a 1,500-credit mistake, and the extractor is the only way to move it.
Extraction and installation workflow
- Install the extractor in the machine's module bay or use it from the machine panel.
- Select the installed module you want to remove.
- Confirm the extraction.
- Move the module to storage or another machine.
- Check the bay footprint before reinstalling.
The exact UI varies by build. If the extractor does not appear as an option, check that it is in your inventory and that the machine is not mid-cycle.
Extraction is not a way to duplicate modules. It moves a module; it does not create one. A module removed from a machine still occupies inventory space until you install it somewhere else.
Expansion vs extractor: which first?
| Need | Buy |
|---|---|
| More space in one machine | Module Bay Expansion Kit |
| Move a module to another machine | Module Extractor |
| Reconfigure often | Advanced Extractor |
| One-time move on a budget | Basic Extractor |
| Fit a 2 × 2 module | Expansion first |
Most players need the expansion before the extractor. A larger bay lets you install more modules; an extractor only helps once you have modules to move.
Common mistakes
- Buying a 2 × 2 module before checking the bay shape.
- Using the last Basic Extractor charge on a cheap module.
- Expanding a machine that is not a production bottleneck.
- Assuming the expansion adds modules; it only adds cells.
- Forgetting that the kit is a random stock item, not a guaranteed purchase.
FAQ
How many cells does a fully expanded bay have? 35 cells, the full 7 × 5 grid.
How many expansions does a machine need? Two to reach the full 35 cells. The first takes it to 31.
Where do I buy the Module Bay Expansion Kit? Dr. Jackson, Monday Special Stock, and the Serpico reward are the reported sources.
Is the Advanced Extractor worth 350 credits? Yes, if you plan to move expensive modules more than a few times. It has unlimited uses.
Community source: community module testing, in-game vendor stock, and the Steam Community guide hub ↗. Store reference: Probably Stolen ↗. Workshop example: Pen's QoL Tweaks ↗.
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