<br>What is Blue Light? <br> <br>Blue light has a short wavelength and is likely to scatter, causing fatigue of the ciliary muscles, which are the adjusting muscles that adjust the lens, and may cause eye strain. <br> <br>Blue light can cause a wide range of risks including eye strain, sleep disorders, damage to the retina, dry eyes, stiff shoulders, and headaches. <br> <br>For those who operate smartphones and PCs or watch TV, it is recommended to take measures immediately with blue light blocking glasses. <br> <br> ● Eye and body strain caused by blue light <br> <br>Blue light generated from PC and smartphone monitors causes health problems such as eye strain. <br> <br>SIGVAN Blue Light Blocking Glasses protect your eyes from all the blue light and UV rays generated in daily life, and prevent various health hazards. <br> <br><br> <br>Material:Plastic, which has the characteristics of super lightness, abrasion resistance low friction coefficient and so on.<br> <br>Note:<br> <br>Due to the differences between different monitors, the picture may not reflect the actual color of the project. thank you！<br> <br>It is a size used for manual measurement and may have an error of 0 to 1 cm, which is normal.Please refer to the actual size. <br> <br>We will do our best to solve any problems and provide you with the best customer services.<br> <br>Thank you so much for support us!<br> <br><br> <br>HOW TO CARE<br> <br>Never wipe the lens when they’re dry.<br> <br>Please use neutral detergent or soap water to clean, gently wipe dry with a clean soft cloth.<br>