Febreze Deodorante per Ambienti a Spina, Unstopables Fresh Scent, Neutralizzatore di Odori Forti, 1 Diffusore + 2 Ricariche d'Olio

The fresh scent from this plugin actually sticks around for weeks instead of fading after a few days like others I've tried. Having two refills in the box means I don't have to think about replacing it for a while.

I stuck this in the hallway outlet near the litter box and it genuinely killed the smell within a day, not just masked it. The warmer itself is small enough that it doesn't block the second plug, which was my worry.

The fresh scent actually lasts the full refill instead of fading after a week like my old ones. I plugged it in near the litter box and it kills the smell completely, not just covers it up. Two refills in the box is a nice bonus too.