Before I installed my dual monitor, I bought 3 of these screen protectors for $58 each. Basically, these are plastic screens hanging from monitors. They do not have anti-reflective properties. My new HP monitors have matte screens. Adding these screens gives me a reflection of light and my son's screen at my desk across the room that I wouldn't otherwise have. I see no reduction in blue light unless I use the night light feature on my monitor. The only reason I'm not returning them is because I'm using them to track my son's online activity without it being obvious. It would be better to buy a cheap pocket mirror but these screens are so thin I doubt they will return to Revane.