UV 400 indicates an eye protection item that has been optimized to prevent eye exposure to both UVA and UVB radiation. Eyes are exposed to sunlight could be at risk for serious damage to their eyes, which can lead to a number of issues including cancers of the eye, vision loss, cataracts, and blindness.
Safety Planet provides different lens types with UV protection: UV 400 Cycling Glasses, UV 400 Glasses for Outdoor Sports, UV 400 Ski/Snowboard Goggles.

Lenses in sports eyewear usually are made of polycarbonate. Since polycarbonate is such an impact-resistant lens material, it works well to protect eyes from fast-moving objects. Polycarbonate lenses are up to 10 times more impact-resistant than plastic or glass lenses. They are also lightweight, strong and durable. Polycarbonate lenses set the standard in eyewear safety. These lenses are a smart choice for athletes, those who work in hazardous job environments.

Removing eyewear to wipe away fog can expose your eyes to potentially dangerous hazards and debris in your workplace. Anti-fog technology help people see clearly.
Fog Free can be applied to plastic, polycarbonate and other eyeglass lenses, including high-index lenses and Transitions photochromic lenses. Your lenses and vision stay clear when you make the transition from a cold environment to a warm one. It may also keep your lenses from fogging up during sports and other times you are hot and perspiring.

Lenses that are treated front and back with a clear, scratch-resistant coating have a much smoother surface that is more resistant to scratching.
The coating does not interfere with how the lens functions and does not affect vision. Though an anti-scratch coating is not 100% scratch-proof, but it helps to prevent minor scratches that can easily happen to a regular lens. These minor scratches can damage the surface of the lens and impair vision. An anti-scratch coating acts as a protective layer thus making the lenses more durable and safe.

Polycarbonate is the material favored by most sports eyewear manufacturers because it's very light and shatterproof, which is an impressive impact resistant lens. Being flexible is what enables it to absorb energy without fracturing. Polycarbonate lenses are more impact-resistant than plastic or glass lenses. PC lens provide a very high degree of eye protection.