This is a non polarized UV400 amber copper driving lens flip up that clips onto a square shape pair of prescription glasses. It comes in a smallest size, small, medium (most popular) and a large size (Note Very Big). Flip-ups work best for glasses that closely resemble the shape of the flip-up. It also fits best if the frame is straight across the top so that when the flip-up clamps onto your glasses it is sitting straight across the top of your glasses. Measure your glasses width x height. It is best to add about 2mm's to the height of the flip up height to accommodate for how the flip up clamps onto your glasses. It is usually okay for the flip up lens to be a little wider or higher than your glasses, it will just overlap a little.
Available Square Flip Up Sizes
One Lens 54mm Width x 45mm Height
Total Width 125mm x 45mm Height
One Lens 60mm Width x 47mm Height
Total Width 130mm x 47mm Height
One Lens 63mm Width x 54mm Height
Total Width 138mm x 54mm Height