Meissner filters for critical applications are constructed with absolute-rated filtration media. All components are thermally bonded without adhesives or hot-melts. These filter cartridges deliver high flow rates with low pressure drops. They withstand repeated sterilizations and sanitizations, while providing extremely low extractables and high dirt-holding capacity. Our graded-density polypropylene microfiber filters are distinguished by their absolute particulate ratings, which are maintained even under the most severe process conditions. Fully automated production gives Meissner filter cartridges the most uniform, consistent construction and performance available anywhere. Assembly, testing and packaging of Meissner filters are performed in an ISO Class 7 cleanroom. All Meissner products are constructed with materials that meet FDA requirements for food contact use and are biosafe in compliance with USP Class VI Plastics biological reactivity tests. Pleated membrane filter cartridges are available in PVDF, PES, PP, PTFE. Pleated prefilter cartridges are also available in PP microfiber media and glass microfiber media, as well as PP microfiber depth media.