Over 30 years ago, Smith Optics introduced Turbo Fan technology. They now incorporate this fog-killing innovation in the Elite Tactical Core product line. A micro electronic fan efficiently and silently evacuates moist air from the goggle chamber to keep you fog free. Our system exhausts 50% more air volume at a 40% lower decibel level than the competition. So sweat it out. The OTW Turbo Fan will be there to keep it under control.