this reading glasses is comfortable and adjustable Vision the yellow line is the demarcation line. They can help first-time buyers how to wear the glasses. You can use the glasses cloth around your nails and then take it out .don't worry that your glasses will scratch, our lens are hard. Note: This is not sunglasses! ! !This Reading glasses outdoors When the ultraviolet light is stronger, the color change is deeper. On the contrary, the weaker the ultraviolet light, the lighter the color change. Photochromic lenses are also referred to as light-sensitive lenses". Glass lenses are adding silver halide, but now is the mainstream of photochromic resin lenses, adding of spiro and other chemicals in the acrylic resin lens, so that the original colorless and transparent lenses, in bright light, will become colored lenses, to do the protection, so is suitable for indoor and outdoor use. Lightweight and comfortable for prolonged wearing. Support Wear together with your own eyeglasses Environmentally friendly material lens,aspherical wear-resistant transparent and clear,protect your eyes when reading.Standard pupillary distance and accurate magnification,to ensure that wearing will not be dizzy,can effectively help glasses to read For new wearers,How to adjust quickly to your new Progressive Lenses: The top region of your is for distance vision, and it provides the most visibility. As you look farther down, the lenses magnify,allowing you to see better up close. To look at an object, turn your head and look directly to ward it (do not just turn your eyes). Then simply raise or lower your chin until the object comes in to focus. Adaptation process: first try to sit on a clearTV-then sit and read a book clearly-then try to wear it when walking indoors-then go up and down the stairs-and finally wear it when walking outdoors. Take a break from your progressive lenses if it feels like they’re hurting your eyes. Then, reapply them. It’ll get more comfortable to wear them over time. When you first get this type of eyewear, you may experience blurry or distorted vision. However, the more you wear the lenses,the faster these symptoms will subside. Give them a chance to work. You’ll be happy you did. For experienced wearers： A new pair progressives – even in the same – can still have a slight adaptation period. This is because no two pair of progressive glasses are the same. For example, some people are more sensitive to viewing through multiple areas in a small lens, so switching to frames with a larger lens size can provide greater comfort and ease in adaptation. Note: While most users have great success with wearing progressives, they aren’t for everybody. If you’re still having trouble adapting after a couple of weeks, with headaches or feeling off- balance, to return the product and choose our other styles to try.