What style of helmet pre-dated the distinctive design used by the German army, a pin of which was given to First World War veterans by the Nazi Party? 
Steel Helmet Veterans Memorial Badge: The Steel Helmet Veterans Memorial Badge was a pin issued by the Nazi Party to veterans of the Stahlhelm veteran association of the First World War. Stahlhelm: Stahlhelm (plural "Stahlhelme") is German for "steel helmet". Stahlhelm:  The Imperial German Army began to replace the traditional boiled leather Pickelhaube (spiked combat helmet) with the Stahlhelm during World War I in 1916.
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