i have never seen one before but it look period originial but hard to tell since i dont know what one of theese should look like
I'll move this one here to see if it gets any more responses......
Looking for LDO marked EK2s and items relating to U-406.....
I have no opinion wheter its original or not, but its likely a badge/'Tinnie' celebrating the 'Battle of Jutland,' which the Germans call the 'Skagerrak Schlacht.'
EDIT: Also check out this thread: