This is my newest addition to my collection. Its a Navy helmet made by an Austrian company.
Don't know yet what the letters WWEU stand for. Thanks to a fellow helmet collector, Have a look at his blog www.casquescollection.skyrock.com
I now know these letters stand for Ulbricht Witwe . This company still exists see: http://www.ulbrichts.com/protection/produkte/
ZM/FN = ZeeMacht / Force navale