Made by Essilor, the world's leader in eyeglass lenses. Crystal Vision Polycarbonate lenses for bifocal vision distance viewing means that the reading area has a half moon shape with a "flat top", in the bottom area of the lens. The Polycarb flat top 28 bifocal has a reading area that is 28mm wide at the top. This is a good choice for prescriptions up to Plano up to +3.00 sphere; above that, we would recommend a higher index lens in order to reduce the thickness and weight of the lens. This lens is available in the following range: Plano to +3.00 sphere, and an add range of +1.00 to +3.00 add. Crystal Vision lenses are made by one of the world's largest lens company making top quality lenses. All Crystal Vision Lenses are made in the U.S., to exacting specifications, in an Essilor laboratory.
