Our Whatman hydrophobic venting filter range consists of Polyvent and Sterivent options. Polyvent and Sterivent are available in disc and capsule formats ranging from 25 mm discs to large size capsules. Our HEPA-VENT and HEPA-CAP ranges with glass fiber filter media are available as 50 mm discs and in three capsule sizes. Many of the capsule vent filters come with a variety of end fittings for easy connections.Whatman venting filters are products for venting air/gases from vessels or tanks while keeping contaminants such as bacteria or particulates out of the vessel. Hydrophobic vent filters with PTFE membrane work bidirectionally to keep the product inside the vessel and keep contaminants out when draining or filling vessels like fermentation tanks. Vent filters with glass fiber media and HEPA retention allows clean air to pass in and out of vessels such as incubators.