plastic fan guards: 1.For computer fan,power supply,filter 2.Material:plastic UL 94V0 3.Size:30mm to 150mm ... 4.Color:balck filter guards 70mm: 1.For cpu cooler,computer fan,power supply2 ... .Material quality:plastic or iron4.Product structure:screw holes,filter,bulk5.the filter including filter cotton,can disassembly for easy cleaning,recycling6.functions ...