Transitions lenses are indoor lenses that darken or "transition" to outdoor lenses when exposed directly to UV light. A Transitions lens can be a good option for some people. They do darken outside and double as a pair of sunglasses. The darkening transitions element within the lens won’t impede your regular vision, indoors or out. However, it is important to know that transitions only darken when directly exposed to UV light. They do not darken in bright indoor light or inside cars. Even outside it will not feel as dark as sunglasses or our outdoor tint. The baseline indoors is a very light pink tint. Transitions may take up to 5 minutes to fully "transition" from indoors and outdoors. Transitions are more reactive or transition faster in cold weather. Indoor temperatures and warm outdoor weather will be slower. Also, our SpectraShield tinted lenses with premium coatings will be comparably slower than other transitions that are not tinted or coated. Transitions are available without the coatings if you prefer, but most customers opt for 2 separate indoor and outdoor frames.