A fiberglass toe cap and cushioned, double density slip resistant sole keeps the Krypton Safety Boot light, flexible and ultra durable, so you can keep stable and comfortable on your feet all day - The double density PU sole consists of an enormous soft and cushioning PU midsole and a very flexible PU outsole. - The flexible anti penetration midsole made from ceramic-coated fibres, protects the feet completely from penetrating objects. - The hard-wearing honeycomb structure of the iCell element improves the cushioning while enhancing the shoes stability, guidance and comfort.