Original: In contrast to the black-uniformed Allgemeine-SS (the political wing of the SS), the Waffen-SS (the military wing) evolved into a second German army aside the Wehrmacht (the regular armed forces) and operating in tandem with them; especially the Heer (German Army).
Simplified: In contrast to the black-uniformed Allgemeine-SS, which was the political wing of the SS, the military wing was called the Waffen-SS, which evolved into a second German army within the Wehrmacht.