D.e.v.s dual exhaust venting system dual exhaust system, Back vent negative pressure exhaust, Speed up the inlet velocity of the forward pores, Quick gas exchange inside and outside cap, Top vent design to increase the range of gas flow in cap, Full head cool evenly, The cooling is obvious. New design top ventilation switch, using force-saving press to open, depending on the user's demand operation increases and decreases the amount of air intake. The vent on both sides of the forehead and chin can introduce abundant cold air directly, and reach the fluidity through the cap body, achieve excellent ventilation effect. Chin ventilation switch, which provides the user with the required intake to allow the ride to have excellent breathing conditions while achieving rapid fog removal Lining design Five type washable lining new, sol sf-5 full cover helmet liner industry only use polygene silver ion+nano bamboo charcoal+coolmax Polygene silver ions can penetrate bacterial cell membranes to kill bacteria and destroy bacterial reproduction mechanism to achieve antibacterial effect. Nano bamboo charcoal fiber can absorb human heat and radiate far infrared radiation, effectively promote blood circulation, and have remarkable antibacterial effect, with 4,0 antibacterial value. Above, eliminating rate above 80%, with coolmax®The cloth takes away the moisture from the head immediately because of sweat, which keeps the head cool and dry and antibacterial deodorant.