We have put your lenses on a diet! High Index Lens materials from Carl Zeiss can make your lenses much thinner and lighter. How? As their name suggest, "high index" lenses are made of materials with a high refractive index. This allows us to make lenses with higher powers thinner - and thinner also means lighter. Depending on your prescription, you can choose between 4 glass lenses and 3 plastic lenses with high index properties. Ask us - we will be glad to advise you.  We may even let you trade in your old "framed ashtrays" or "coke bottle bottoms".