Hard coat coating
Single vision lenses have the same focal power throughout (top to bottom) and can be used to correct nearsightedness, farsightedness, astigmatism, or a combination of these disorders. Most people who wear glasses before the age of 40 have single vision lenses.
It is the most common lens material used for eyeglasses, it is lighter in weight and less breakable than glass.  You may tint these lenses almost any color.