The Iron Cross was an award of bravery, equal to the american purple heart.
The TOTENKOPF, "Death's Head" used as a symbol for the SS branch "SS Totenkopf."
The general symbol for the Schutz-Staffel. The two S's are ancient germanic symbols which stand for victory at any cost. The symbols work out well because of the term Schutz Staffel beginning both its words with the letter S.
The Iron Eagle holding a Swastika was the National Symbol for the 3rd reich. The Eagle being made of Iron was to represent the "untouchable" strength of the German military and people at the time.
