This helmet cover known by the name “Mitznefet” and it used by the IDF.
Even though you not in special forces, you still might want to wear this to hide from the enemy by changing the shape of your helmet and add camouflage pattern to it. If you’ve recently served in the military and have worked with any of the Israeli infantry troops, this helmet cover is familiar to you.
Owing to the fact that it flops around as you move it prevents your helmet’s outline from throwing a clean-lined shape, making it more difficult to notice it. Its color and shape blends in the desert terrain as mountains and sand.
It has to do with the belief that if you have effect of surprise you have the upper hand in combat, this helmet cover was developed for the IDF to be used in desert terrain to keep the IDF troops from being discovered.