E-PAC® was originally developed at Hewlett-Packard, Boeblingen in 1991. The chassis concept is based on form fit to eliminate the screw count in your product
dramatically. The concept immanent tolerance issue caused by over designed features was first solved by using the material EPP (expanded polypropylene). The concept was originally published under
"Schäumen statt Schrauben" - literally "foam instead of screws".
HP Journal Article
Background info about the development at Hewlett-Packard in Boeblingen, Germany.