Recently I came across an Oldenburg NCO Pickelhaube. This helmet is in near mint condition and has a woolen liner. Production date 1914-1915 I guess. The odd thing is that the inner side of the front visor has a black coulour, instead of the usual green one's I have seen so far. The backside has the regular red colour. It all looks original. Are there samples known from litterature, or is this the first one that comes along?