When you want to buy a pair of eyeglasses, the material of frames is very important for you. Some kinds of materials are very light and suit your face skin. Nylon frames is a common material which is suitable for children, because they are hard to break. And Flexon frames are the good choice for the people who need flexible frames. If people want to wear a light frame, the titanium frames are the nice choice for them. Especially for people who have the sensitive skin. Such as me, once I wear metal frame, the skin of my face will appear many red measles. But using pure titanium frames, it is very comfortable.