The Sawyer MINI water filter is rated at 0.1 micron absolute, weighs just 50g, and filters up to 350,000 liters.
The MINI can be placed in the included collapsible bag, creating a hydration pack, keeping a standard soda bottle close at hand, or simply using the straw to drink directly from the water source. Why is it so versatile? Like all Sawyer filters, proper flushing can restore up to 98.5% of filter flow. That means there are no parts to replace.