It does what!?
Pump filters are on the way out! Why pack that heavy 3 liters of water in your hydration pack when your hiking along a stream or river? Just carry this 4 oz kit (filter and 1 oz bag) and fill up when you're thirsty and drink.
I also made this into a drip filter with the sawyer adapter kit (cheap but not carried by bc.com yet) for when I'm relaxing at basecamp. Leave time for the more important things when you're in the backcountry with your partner ;).