The gray lens does not change the color of the object while filtering the amount of light passing through the lens. Lenses of other colors, even black, have little Sunglasses Sale effect on the color of the object.
The frame for glasses must be made of lightweight material, so that the child does not feel the weight of the sunglasses, it is more comfortable in it.
Are you crazy, contemporary, geek or preppy? Each style has a different recipe nuance available depending on this taste.