After seeing Brandito's DeWalt Tough System Organizer Nested Cups, I thought: "why not do the same for the Milwaukee Packout organizer bins?"

This nesting cup fits into the small Packout bin and rests on the narrow diagonal lips in the corner of the bin. This allows you to fill the bottom of the bin and then drop in the nesting cup on top for more organizational options.The divider is somewhat necessary for pulling the nesting cup out as it has to sit below the edge of the bin due to the was the lid closes.

Right now I only have the one nesting cup design for the smaller Packout bin. If there's interest I could make deeper or shallower cup, one with more dividers, or even a cup for the larger Packout bin.

The reason I didn't include any more cup variations or make a customizer is the fit is very finicky. Packout bins have a taper to the sides and I didn't want to post anything I didn't test first.

I made the model in Fusion 360 and am including the STEP file if you want to make modifications.

Check out my Packout Middle Bins and my Packout Low Profile bins

Update 1: I added half height cups with 2 and 4 compartments. It is half the height of the usable space inside the bin.

I test printed a cup and it is a really snug fit. If your printer prints a little big or you have some z-axis banding, they might not work. I finally figured out how to do tapered extrusions, but it'll be a while before I can test print one.

Update 2: I added cups for the bottom of the bins. Now you can divide the bottom into 2 or 4 compartments. They also fit in the large bins, and when you do you can also use the stacking cups. I figured out how to taper the sides so the bottom cups are tapered.