This is an open differential with helical gears. Open not only because you can see the gears, but also because it's opensource. The 3d model goes with it, so you can change what you want and add features.

This is my take on Differential Thing by orcanicap (https://www.thingiverse.com/thing:3592644) that ended up in a complete rebuild.

The pinion (Pinion.stl) and the base (base.stl) possibly need supports. But its minimal. The other files doesn't.

The shafts (ShaftSet.stl) are sized exactly to the diameter of the holes, so it won't fit the way they are in the file. You'll have to use horizontal expansion in your slicer. Or else sand the pieces by hand...

Using PLA on my printer, -0,18mm expansion was enough for a good fit.

I've chosen to do this way, cause it's hard to account for the huge amount of possible settings regarding the printer and material being used, so that you can use what works better for you.

Software used to open the model:

• FreeCAD 0.19 (https://www.freecadweb.org/)
• Addons: Gears workbench and A2plus assembly workbench