One of the main causes of hardware unreliability is heat, & the biggest cause of gradual increase in running temperature is the accumulation of dust. As dust builds up around sensitive components inside the case, cooling is reduced, fan noise increases & the system could start to slow down. Dust can even be slightly conductive & this, combined with a hotter running temperature, may eventually cause hardware failure. Of course, the best solution is to prevent dust entering your system in the first place, & so we are pleased to present these magnetic computer dust filters which will keep dust & dirt out of your IT equipment. Your PC will run cooler & will last longer, saving you money & making maintenance & any future upgrades of your computer much more pleasurable. This is definitely a case of "prevention is better than cure"! Even if your PC doesnt have a fan installed in a certain position, but there is still a grille opening to allow airflow & possible later installation of a fan, it is still worth considering adding a filter to the open grille. The reason for this is because there will still be a likelihood that air (and therefore dust) will be entering the PC case at that point. This airflow will be caused by negative pressure inside the PC case which is brought about by other fans in the PC, such as the power supply fan & even the processor fan, which all serve to move & ultimately expel air from the case. ** High Precision Polyester Mesh** Dust is prevented from entering the PC by a high precision polyester mesh. This super fine medical-grade mesh is the same material which is used in hospitals use to keep dust out of operating theatres. The filament diameters of this mesh are smaller than the openings between them. This allows more air through the filter while still stopping the dust. These filters are the only computer dust filters we have come across that guarantee to keep out specific size & larger dust particles due to