Amazon has lots of these. Have herd the glass breaks very easily. 

I just don’t see any other benefit in it.

We have a number of these and similar items. Let's see if this helps:

5 is a ceramic disk with a cotton coffee filter fitted over it (7 is a spare filter). Put 5 in 3, filter up. Pull the spring-loaded hook down and hook it on the bottom of 3. Put ground coffee in the top of 3.

Put the water in 2, then fit the 3/5 assembly into 2 with the red rubber gasket (6 is a spare gasket) making a good seal.

Place an alcohol burner under 2 and light it. The water will eventually boil and be forced up through the bottom of 3, through the filter and into the upper chamber of 3 where the coffee is. Allow the water to continue to bubble for the desired time- longer = stronger coffee. When that time is up, extinguish the flame.

As the air and residual water in 2 cools, it will suck the coffee down from the upper 3 chamber, through the filter and into 2.

Carefully remove the 3/5 assembly from 2 and place 3/5 in stand 4.

You can now grab 8 by the black handle and pour coffee from 2 into 9, the unseen coffee cup.

Though I did number 1 and 2 differently, they're basically the same thing 1/8 is a spare. Why I did that and left the stands as both 8 is a mystery! LOL! 2 can be removed from 8 once cool by loosening the knurled nut behind it, which will loosen the clamp on 8 that holds 2.

Hope this helps!

Chuck

That is FAR from the original burner. Sorry.....  I'll see if we have one I can take a picture of.

However, it may work!

Chuck