Due to people have different sizes of heads and different shapes of faces, the eyeglass frame have to be customized made to fit individual's requirement. It is important for you to know the numbers on the eyeglass frame. The first number on your eyeglass frame is 55, which means your lens size is 55. And number 17 indicates the bridge size, that is to say, the fit distance between your nose is 17. The last number stands for the temple length, which indicates the fit over your ears is 150.
When you see the numbers on the glasses frame, it means the lens size, bridge length and arm length. In order to make the eyeglasses suitable for you, the eyeglasses are designed in the detail with different sizes according to your face size. Owning these sizes, you will not have the eyeglasses slipped off easily.