Subtle details and technical features are carefully considered for fit, proportion, and comfort. GLCO demands a high standard of perfect quality to guarantee their customers the ultimate value in quality and style. They spend years mastering the intricate details of a GLCO frame with their factory partners before releasing a frame to market. GLCO uses the most exclusive, highest quality materials from the best suppliers in the industry with hundreds of years of experience. The cured acetates, ranging from deadstock to colorways exclusively designed and produced for GLCO, are sourced from the top acetate houses in Japan, Italy, and China. GLCO's lenses are made of mineral glass and scratch-resistant CR-39 plastic, with anti-reflective coating and other treatments such as layered mirrors for the best eye protection, clarity, and visual acuity.