1.Screen Magnifier Size: 21' Large Size Universal Screen Magnifier is suitable for Laptops/Tablets/Mobile Phones. 19' x 14.3' (50x36.5cm), the screen is 21 inches. Watch 3D movies or study work: You can easily enjoy the home theater-like effect. The HD image is clear and realistic, which solves the problem that the mobile phone notebook screen is very uncomfortable and effectively protects eyesight. It is different from all the screens on the market. Our screen is developed. 2. Protect your eyes: The screen magnifier is made of high-definition optical lens material, which can magnify the mobile phone screen by 3 times and can adjust multiple viewing angles. It can enjoy 3D vision away from the screen and relieve the discomfort and visual fatigue caused by focusing on a small screen for a long time. 3.3~4x Magnifier: The magnifier in your hand can reach 3x magnification. 3x magnification is considered to be the most comfortable magnification when reading small fonts. Made of durable ultra-high-definition acrylic Fresnel lens + environmentally friendly wooden frame, made of high-quality materials. 4. Watch 3D movies or study work: You can easily enjoy the home theater-like effect. The high-definition images are clear and lifelike, which solves the problem of discomfort when watching mobile phone and notebook screens and effectively protects eyesight. It is different from all the screens on the market. Our screens condense many years of optical technology, and you will not feel dizzy no matter how long you use it.