Want to thank you all for your nice comments!
Here is a intresting link (sorry but is in French) regarding the M15, and when you scroll you will find the "commercial" Adrian helmets made from cork, felt and alu.
http://www.world-war-helmets.com/fiche.php?q=casque-francais-adrian-mle-15" onclick="window.open(this.href);return false;