These cheap foakleys Glasses are also known as progressive Oakleys Glasses, as the power of the lenses increase gradually from the top towards the bottom. Varifocal Oakleys Glasses have a gradually increasing power on their lenses, with the top part of the lenses having the lowest power and the maximum power at the bottom most part. When one has to look at objects at the distance, the upper part of the lenses is used. For purposes like reading foakley sunglasses or looking at close-by objects, one just has to look through the lower part. The intermediate part of the lenses can be used to view objects which are located at an average distance.While buying cheap varifocal Oakleys Glasses, you must keep in mind your face structure.