Variable light conditions can really affect how much fun you’re having. When the light changes, you want to make sure you’re prepared with the appropriately tinted lenses or that you're equipped with so called "All Conditions Lenses" able to handle most weather, terrain, and conditions. Each lens has a Visual Light Transmission, or VLT, percentage unit that describes how much light will go through the lens as measured in a lab test. The higher the VLT percentage, the more light goes through (a high % is usually ideal for dark conditions), the lower the percentage the less light goes through (a low % is usually ideal for bright conditions). The VLT percentages can also be classified under 5 categories: