Cyst Filter replacement cartridge for Exstream Water Purification Bottles

- Filters sediment and protozoan organisms such as cryptosporidia and giardia
- Package of 2 filtersExstream Water Purification Bottle

Maintenance:

- Change the ViruStat Cartridge after 200 refills.
- Change the Cyst and Pre/Post Filters when water flow becomes constricted.