MetaPurex nano-porous aluminum oxide (AAO) ceramic discs can convert your standard Buchner filter into a nano-filtration device. Fits selected Buchner funnel filters, 65 mm diameter. Pore size of 60 nm with a maximum variation of 10%. Membrane thickness is 50 microns. Micro-crack free heat sealed edges requires no o-ring protection, providing an effective larger filtration surface.