Metal sunglasses means that most sunglasses frames are made partially of metal and may use other materials in the footwear or other decorative parts. Metal sunglasses are the most common and durable and most used for sunglasses. Such as aviator sunglasses, etc.
Metal sunglasses frames tend to be lighter and more durable than acetate or other blends because of the material, so if you use them in relatively harsh environments, such as being outdoors a lot, in the jungle, and the sun for long periods, we recommend metal sunglasses as your first choice.
As the most stable material, metal sunglasses frames can last at least 1-3 years at a time, and with careful use and preservation, some can last more than 10 years intact, during which time, of course, the sunglasses lenses still need to be replaced.