NoIR Sunglasses offer 100 percent ultraviolet protection, 87 percent light transmission and 100 percent blue light protection. They heighten contrast, feature maximum brightness and good visual acuity. The SpectraShield frame has a ledge at the top to keep the sun or light from beaming in and it has windows on the sides of this same filter for complete protection from the sun and artificial lighting. These sunglasses can be worn alone or over prescription glasses. Offered in medium which measures approximately 6.1 inches wide. Useful for macular degeneration.