You might be thinking of this product: https://www.amazon.com/Litter-Care-Non-Stick-Coating-Enclosure/dp/B078GXDGDN/
This is another option that people have used successfully: https://www.amazon.com/gp/aw/d/B084TNCT28/
Howard Products WAX009 Food-Grade... https://www.amazon.com/dp/B084TNCT28?ref=ppx_pop_mob_ap_share
Litter Care - A Non-Stick Spray... https://www.amazon.com/dp/B078GXDGDN?ref=ppx_pop_mob_ap_share
I used the wax on the hard plastic and the spray on the rubber dome part