1、BLUE LIGHT BLOCKING: Laptop blue light blocking filter film filters harmful blue light with wavelengths between 380‑420nm. Blue light blocking technology protects your eyes, sleep and skin from the negative effects of excessive blue light exposure. 2、UV PROTECTION: The screen protector also filters out 99% of harmful UV rays. to help reduce eye strain. Used for a wide range of HEV protection and is compatible with 21.5in (Approx. 491x288mm/19.33x11.34in) laptop screens. 3、EYE PROTECTION: Laptop blue light blocking filter film allows you to enjoy your digital time without worrying about eye strain, blurry vision and Provides you with better sleep, blue blockers for your eyes and protection for your health. 4、HIGHLY TRANSLUCENT: Laptop screen protector is made of highly translucent acrylic to protect against screen dust and scratches. Perfect for students, OL, gamers and programmers in the office/home. 5、EASY TO INSTALL: Laptop screen protector is very easy to install, after cleaning the monitor just remove the film on both sides of the computer screen blue light blocker and hanging it on the top end of the screen, easy to remove. Item Type: 21.5 Inch Blue Light Blocking Screen Protector Material: Acrylic Product Size: 21.5 Inch (Approx. 491x288mm/19.33x11.34in) 1 x Protective Film 1 x Cleaning Cloth