Sawyer Single Mini Water Filter

The Sawyer Single Mini is a 57 g hollow-fibre squeeze filter with a 0.1 micron absolute pore size, tested to remove 99.999% of bacteria and protozoa. It threads onto standard 28 mm PCO soda-bottle necks, is compatible with hydration bladders, and can be backflushed in the field with a syringe to clear out sediment and restore flow — Sawyer rates the cartridge for up to 378,000 litres when maintained this way. It's small enough to fit in a palm and squeeze-operated, so it works well as a solo or lightweight filter for streams and lakes on trail, but it isn't freeze-resistant — trapped water in the fibres can crack the membrane if it freezes, so it needs to be kept from freezing overnight in cold conditions. For hikers who want a compact, long-lasting filter for personal use rather than filtering for a group through gravity or pump systems, it's a solid minimalist option.