This tool is used to align an MGN9 Linear Rail on a 2040 Aluminum Extrusion. The tool helps you align the rail on a single 20mm lane of the 2040 extrusion.
Personally, this was used to align MGN9H z-rails on a Voron Trident EZ-Bake (Doomcube Variant for Trident).
The author marked this model as their own original creation.