Suppose you ever had anything to do with helmets. In that case, you probably know that they can cause all sorts of troubles to your head: not only with their weight but also because they cause skin irritation by rubbing, or just not offering any insulation against cold or heat. Of course, they will not let rain through, but that’s where their protection against the elements ends. The most important thing is that they do not offer any protection against losing heat from our head, through which, as we all know, we lose most of our body heat.