Stainless steel metal combined frame, unbreakable ultralight, and high stress-resistant material ensure the durability- you can use it for many days and also perfectly resolve comfortable wear experience. Good quality steel frame provides the ultimate in performance and comfort, impact, scratch resistant and durable. It provides the best lens and frame combination solution with such a favorable price. Indeed fine and inexpensive choice. Nickel free plating prevent from rusting keep the frame new always. Carefully choose and check the lens before production, carefully handle each process to avoid scratches.