MAGNETIC: 140mm 14cm magnetic fan filter for keeping and protecting your computer and electronics parts clean,no need screws ,easy and convenient installation. SMALLER HOLE: 140*140mm / 5.51*5.51" with pvc thickness 0.45mm Hole 0.5mm(smaller hole for better dust protection) for daily hommization use. PVC FILTER: 140mm 5.51" PVC fan dust filter cover ,reduce the fan and parts cleaning time,prolong working life,even if filter dirty, easy cleaning and replacement. FUNCTION: It can be used for home computer chassis fan dust filter, speaker grilles and other electrical / electronic products speakers dust protection. PACK INCLUDED: 5 x 140mm Magnetic fan dust filter ,if any other questions,please feel free to contact us to get the prompt and detailed reply.