Plastic sunglasses are not only a fashionable accessory, but they can protect your eyes from harmful UV rays. Sunglasses with UV protection can prevent cataracts, skin cancer around your eyes, and even loss of vision with old age; this is why it is important to wear sunglasses when you go outside. Don't let owning a pair with loose and uncomfortable frames become an excuse for why you never wear your sunglasses--there is a quick and easy fix that will have your frames tightened in no time.
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Open your glasses, hold them as though you are going to put them on, and place them down on a solid surface.
Find the hinge where the ear piece connects with the eyeglass frame on each side. Looking down at your glasses, take note of the tiny screws that hold the hinge in place. You may choose to use a magnifying glass to do so.
Using the tiny screw driver from your optical repair kit, tighten the screw on one side by turning it to the right until you feel resistance. If the screw is missing, use one from your optical repair kit to join the eyeglass frame with the ear piece.
Repeat Step 3 on the opposite side.
Try on the glasses. If they still feel loose, repeat Steps 3 and 4, tightening the screw a little past the resistance point.