The in-ear phones are created by 3D scanning the wearer’s ears for a perfect fit.
Therefor the eFit 3D scanner developed by United Sciences captures the surface of the ear within a few minutes. The 3D model is then used to 3D print a mold, that will be filled with silicon. Harman uses the MakerBot Replicator Mini 3D printers to simultaneously create all the separate parts of the mold.
The whole process takes about an hour and is demonstrated in the following video: