In the constant struggle to reduce my pack weight I have been looking at gravity filter, specifically the ULA Amigo water filter.

I know that the Amigo uses the filter from a Pur/Katadin Hike water filter which I already have and use. I was wanting to make the gravity filter using the filter out of my Pur Hiker. The water bag portion of the gravity filter would be pretty easy to make and I already have the material to do so.

I was mainly worried about the middle section of the gravity filter, the section where the filter attaches on the inside of the bag that leads to the output hose on the extreior of the bag.

Is there something that I can buy and use in this section or would it just be better for me to buy an Amigo minus the actual filter?

Has anyone ever made their own gravity filter? Are there plans available?