1.5 Index Lens is standard
A lenses index defines how thick the lens is, the higher the index the thinner the lens. We offer three different lens indexes 1.5, 1.59 & 1.67. As your prescription becomes stronger the lens becomes thicker, therefore stronger prescriptions should be using higher index lenses to reduce their physical thickness.
Low prescriptions (Up to +/- 4.00)
A 1.5 index lens will be fine, however if you are after a thinner/lighter lens the 1.59 index is a great upgrade.
Mid range prescriptions (Up to +/- 6.00)
A 1.5 index may become quite thick & therefore we would recommend a 1.59 if you are wanting your glasses to look the part.
High prescriptions (Over +/- 6.00)
At a minimum we would recommend a 1.59 index however 1.67 would be more suited.