A notable example of labour-concentration camp is the Mittelbau-Dora labour camp complex that serviced the production of the V-2 rocket. Extermination through labour was a Nazi German World War II principle that regulated the aims and purposes of most of their labour and concentration camps.[30][31] The rule demanded that the inmates of German World War II camps be forced to work for the German war industry with only basic tools and minimal food rations until totally exhausted.[30][32]