TerrorEyes lenses intensify vision without diopters. They are for cosmetic purposes only,providing a stunning visual effect. The lens is soft textured, and manufactured in Phema (Poly 2-Hydroxyethylmethacrylate). TerrorEyes are produced under ISO International Standards quality control and assurance, and have a CE safety certification. After opening-with regard to the enclosed care leaflet-the lenses are usable for approximately twelve months.They should not be worn for more than three months, and never whilst driving. Each package contains two soft sterile lenses in a buffered saline solution, and detailed handling and maintainence instructions.