Features 1、Blue Light And UV Proof: The screen protector panel features green light coating that effectively absorbs harmful blue light wavelengths between 380‑420nm, guarding your eyes, sleep, and skin from the negative effects of overexposure to blue light. Advanced blue light blocking technology filters out 99% of harmful UV rays to reduce eye strain and fatigue, providing extensive high energy visible (HEV) guard. 2、High Transparency Rate: Compatible with 21.5 inch computer screens, this anti blue light screen protector panel is made from high transparency acrylic that prevents screen dust and scratches while maintaining optimal screen clarity. Ideal for students, office workers, gamers, and programmers seeking a comfortable visual experience. 3、Reduce Eye Fatigue: Enjoy your digital time without worrying about eye strain, blurry vision, or headaches. The computer blue light blocking screen protector provides better sleep and eye guard, ensuring overall health and well being by reducing the negative impact of blue light exposure. 4、Easy Installation: This blue light blocking screen protector is simple to install, just clean the screen and remove the thin film from both sides of the computer screen blue light retardant. Place the protector on the screen with no paste or bubbles, allowing easy removal and transfer to other computers as needed. 5、Anti Fingerprint And Oil Resistant: Enhanced with a hydrophobic and oleophobic coating, the screen anti blue light filter effectively repels fingerprints, dust, and oil, allowing easy cleaning with a single wipe and preventing residuum buildup. Keep your screen clear and no smudges for a consistently pristine display experience. Specification Item Type: Blue Light Blocking Screen Protector Material: Acrylic Suitable Computer Screen Size: 21.5 Inch Approx. 510 x 305mm / 20 x 12in Built In Polymer Lithium Battery: 30mAh Filter Wavelength: 380-420nm blue light (does not filter beneficial light), 99% UV Proof Package List 1 x Protective Film 1 x Cleaning Cloth 3 x Buckles 1 x Blue Light Test Card 1 x Blue Light Lamp 4 x Protective Cases