Review on ThreeBulls 12 Pcs 120mm PVC Black PC Cooler Fan Dust Filter Dustproof Case Cover Computer Mesh - Keep Your Computer Dust-Free and Efficient by Ethan Delaney

100% recommended for all computers. I have 2 dogs in the house and dog fur is everywhere, I installed it on the outside of the case on the side wall with fans as an air intake for the PC. It's been about 2 months since I installed them and the inside of my computer is much cleaner and I don't see any dust build up yet. I'll note that since they're installed outside, I can see what's encased in these things. . Almost every day I can remove a hair/ball of dust larger than a quarter. I was most concerned about the size of the holes, afraid they would be too big to be effective. The pin-sized holes are very small and the loss of cooling air is negligible.