I have been chuckling like a dork at this particular patent since such things first became searchable online, and have never found any evidence of it being manufactured and marketed at all. The "non-adhesive adherence" is illustrated in the diagrams on the patent which you can see at the link. The inventor proposes "a facing of fluffy fibrous material" to provide the filtration and the adherence; basically this thing is the softer side of a velcro strip, bent in half with the fluff facing outward so it sticks to the inside of your buttcrack to hold itself in place in front of your anus and filter your farts through it.

you guys are weird