Learn something new every day. I used one of those about 15 years ago on my Grand Marquis, so I could attach a K&N filter I found tossed on the side of an off-ramp in Worcester. I spotted it weeks earlier .. then one day after pricing those filters out, I stopped & grabbed it. Didn't get rear-ended either! I bought a PVC reducer & attached one end to the filter, & the other to the "sewer pipe coupler" (Fernco) , and that to the stock intake plumbing.
Filter was on there when the car was stolen by Mexicans & lived in for a year, and was on there the day I sold it out in CA.