One of the more “unique” tropical helmets of the 20th century was the variation of the Dutch Model 1927 steel helmet. While many steel combat helmets were used in tropical regions during the Second World War, most were the basic helmet simply worn in that theater of operations.
However, the steel combat helmets used by the Royal Netherlands East Indies Army or Koninklijk Nederlands Indisch Leger (KNIL) were actually developed and produced specifically for use by that military force. Instead of issuing the KNIL with the newly adopted Model 1927 helmet, which was used by the Dutch military in the Netherlands the Dutch Minister of War called the development of a modified version.
While not a “fighting unit” in the traditional sense, the Indian Medical Service (IMS) was a military medical service in British India. Many of its officers, who were both British and Indian, served in civilian hospitals and the unit saw service in both World Wars – with many of its doctors heading to the front lines with the Indian Army. 
