that's the thing! made of flannel. you could conceivably use any fabric, maybe even flax you made yourself. wire and fabric, lasts forever (as long as you don't let it get moldy- they are really easy to clean out if the water is drained).
The instructions are to heat water to 200 degrees (or let it cool a bit after coming to a boil) then pour a little water over the ground coffee in the filter to "bloom" it, wait half a minute, then pour the rest of the water over in a circular motion. People say the coffee thus brewed is delicious, and it goes right into your mug (or you could fill a thermos or a pot, as it can make more than one cup).
Pour-over coffee is all the rage in Portland these days.
Personally, I'm using a manual espresso machine, where I'm literally pulling a shot with a heavy lever. That too, is all made of stainless steel, but we had to look hard to find a good used one on Ebay that didn't break the bank.