The STLs for the Headphones are packed into a single STL file. This is done for versioning simplicity.

Obviously, the pieces have to be split before they can be printed. Cura and PrusaSlicer both have functionality to split STL files with multiple STLs in them into individual STL pieces. We haven't tested other slicing softwares, and they may also contain this functionality. However, Cura and PrusaSlicer have both been tested and verified as working, and both are available for free.
