FastCap Bottle Top Filter ~ The Fastcap filter works on any bottle that has a neck opening of up to 53mm. The FastCap Filter eliminates the need to use threaded glass media bottles. Place a FastCap filter on bottle mouth, attach a vacuum line to the larger center vaccum hose link and your liquid media tube to the smaller tube link and start filtering. The FastCap filters up to 5 liters of liquid. Housing is blue polystyrene; the 90mm filter is made of PES (polyetheresulfone) with a 0.2um pore diameter. The FastCap filter is packaged in individual hermetically sealed plastic bags. FastCap filters are STERILE (gamma radiation sterilized). FastCap filters are sold in individual units or a case of 10.