Frame Size Information
If you look on the inside of the arm of your glasses you find will something that looks like: 52 [] 16 135.
This is information on the size of your glasses: the lens diameter, the bridge width and the arm length, all measured in millimetres.
The Eye Width, or Lens Diameter, is the width of the lens (in mm), measured from the bridge. (In this example, the Eye Width is 52.)
The Bridge Width is the gap above your nose between the lenses. It should be comfortable. Too tight, and the glasses could pinch your nose; too loose and the glasses will not be stable on your face. (In this example, the Bridge Width is 16.)
The Temple Length, or Arm Length, is usually one of three standards � 135, 140 or 145mm. The arm should be long enough to sit comfortably over your ears. Glasses with straight arms do not always have this measurement indicated. (In this example, the Temple Length is 135.)