I've got one, probably the most advanced "simple" system there is. It will filter pretty much anything as mentioned.
It is big and heavy
It is an expensive system to filer 65 gallons of water per cartridge.
You get the amount amount your bottle is, so say 16 oz for cooking and drinking unless you run back and get more or pour the clean water into something else.
With that, it is simple and about foolproof
Those cartridges last 10 years sealed
Pretty sure no damage from freezing
Did I say durable?
I love mine, I used it on hikes and took it to Mexico to use on the faucet water.
I also picked up their "pot" that is designed to nest with the bottle, pot is 1L and is marked as such. Lid has to be stored separate as the bottle sticks out from the pot.
So with a pocket rocket style stove and this, it would make a nice cook set, though heavy.
I too was interested in the filter pore size and just found this, little to much to cut and paste.
There is a wise Hebrew saying which says, "A righteous mouth will bear fruit of wisdom, but the tongue of those who twist will be cut off." (Proverbs 10:31). I first began to hear about The Grayl...
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