This Slit Lamp Lens offers an ideal combination of field and magnification. This Lens provides an extended working distance from cornea.and we sell more than 50 lens by ebay last weak and everybody was very happy after use so we assure best quality with best price,, if anybody want anything related to surgical ophthalmic , dental , scientific and glassware feel free to contact me by ebay i will give you best service with very good price..AJANTA