Purofort contains millions of air pockets. Because they are mixed under high pressure, they are evenly distributed. This is quite unique, as Dunlop is the only boots manufacturer in the world that uses high pressure technology to produce its boots. And it’s very beneficial for you: thanks to the evenly distributed air pockets, Purofort provides extreme thermal insulation, keeping your feet warm in the coldest conditions. And because air and solid material are optimally mixed, Purofort is lightweight and comfortable.