I was fortunate enough to have obtained one of these helmets a few years (14 years WOW) ago. Not easy helmets to find.Recently back from Lisbon where the Museu Militar has revamped one of their galleries, showing this interesting Portuguese General's Filz helm plus an EM from a Rifle regiment. Easy to see from where they derived their inspiration but the very different approach to the scale of the spike /ventilator could perhaps be regarded as a more practical solution than was the case with German Imperial helms.