VINTEZ Universal Acrylic 23, 23.6, 23.8, 24 Inch Computer Privacy Screen Filter for Widescreen Computer Monitors - 21.2" x 13.4" (541 x 342 mm) - Monitor Frame Hanging Type

Already bought 2 of those and are extremely happy since they dim the screen to a level which helps to spend more time in front of your monitor without any headaches caused by the blue light. Customer care in this company is very helpful to a degree that they will send you a new filter when you run out of mounting stickers. Highly recommend!

Works great! I have photofobia, which means light affects me more than it should, especially blue and white lights. For the amount of time spent on the computer, these shields (bought 2) have helped me a lot and reduce my headaches. Also works great for security reasons as you can't see anything from the sides unless you're looking at it from the front.The only negative comment I have is that the bottom part is not flushed with the monitor so i tend to bump it (when reaching for something underneath the monitor) sometimes which makes me realign it again. Other than that great product!