Lens category 0: Fashion spectacles
These are not sunglasses, as they have a very low ability to reduce sun glare. They provide limited UV protection.
Lens category 1: Fashion spectacles
Like category 0 lenses, these are not sunglasses; however, they do provide limited sun glare reduction and UV protection. Fashion spectacles with category 1 lenses are not suitable for driving at night.
Lens category 2: Sunglasses
These sunglasses provide a medium level of sun glare reduction and good UV protection.
Lens category 3: Sunglasses
Similar to category 2, these sunglasses provide a good level of UV protection. Lens category 3 glasses also provide a high level of sun glare reduction.
Lens category 4: Sunglasses
These are special-purpose sunglasses that provide a very high level of sun glare reduction and good UV protection. Never wear them while driving.