Review on 🚽 Enhance Your Cat's Litter Box Experience with 6-Piece Activated Charcoal Filters – Eliminate 99% of Odors – Trimmable Pads for Hooded Litter Boxes by John Hall

I started looking for them when I got the closed shell. The box had a slightly thicker filter than this and conformed to the shape of the box, but I couldn't find refills for it anywhere. I refrained from writing a review until I changed the filter for one of them. They were easy to cut to fit the hole in the box. And after installation, there were no extraneous smells from the box. Since the space was intended for a thicker filter, I folded it up before cutting, so it actually doubled in size. It works.