Applied with a clean, soft towel inside your goggles or face shield, spray- or wipe-on antifog treatments help keep your vision clear when riding in the rain, fog, or low-temperature, high-humidity environments. The reason visors and lenses fog on the inside is because the warm, moist conditions behind the lens (in other words, near your face) surpass the air’s capacity for retaining the moisture as a vapor. Thus, moisture settles on the inside of the lens as a foggy film. Treating the inside of your lenses with an antifog product reduces the buildup of moisture, which in turn helps deliver needed visibility. Treating the outside with a separate water repellent nicely disperses water droplets during rainy weather.