This filter disc is the perfect companion to the Pressure and Vacuum Relief Valve for ensuring that sanitary conditions in the fermenter, stay sanitary. If a vacuum forms in the fermenter and draws air in through the Pressure and Vacuum Relief Valve, this filter will remove airborne contaminants and prevent them from ruining the beer.
It has an OD of 47mm (fits on 1.5" tri-clamp compatible ferrules) and a pore size of 0.22μm (small enough to keep out all microbial contaminants). And it can be boiled in clean water to easily sanitize prior to use.
Note: Filter discs may be packaged with wax paper discs separating the teflon discs—DO NOT use the wax paper discs as filter media as they will not let gas pass through.
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Comes in packs of 25.