The starter kit gets you the diffuser head and one vial of Feliway, which lasts 30 days — and the Prime Day bundle gets you an extra *six months* of refills, so you'll be stocked for a while. If you're not ready to go all-in on the big bundle, this smaller starter kit comes with two vials of Feliway (which will last you two months) for 20% off. Keep in mind that if you're introducing a new cat, you should *still* take proper precautions like keeping them separate for a while, doing smell introductions first, etc.

I recently used this in my apartment because I adopted a new cat (the cute brown tabby above!) and had to do a slow introduction with my resident cat — and I have to say, the day I plugged in Feliway, the hissing from my new cat pretty much stopped. While I was doing other things to help ease the transition as well, I do believe Feliway had a huge impact on calming both of them down and making the introduction so successful (months later, they're basically best friends).

Promising review: "I can’t express enough how much this has changed mine and my cats' lives. Merging two households wasn’t easy on the cats. One male cat had a hard time moving into a new house with new pets. He had terrible behavior problems and would cause us and the other cats a lot of stress. His bullying led to the other two cats having health problems. He would get into moods where he would chase and attack the others and would not let up. We tried everything the vet suggested to reduce theses incidences, but getting Feliway was the only thing that worked. He is a completely different cat now. He is calm and his outbursts rarely happen. He has become a couch cat and has turned into the sweetest boy. We couldn’t believe that this one product could fix everything, but it did. If he starts to act out again we check the diffusers, and sure enough, one of them will be out. If your cats are having any behavior problems or stress please try this!" —Kristine Spencer

Price: $91.98 (originally $114.98), or get the smaller bundle for $36.78 (originally $45.98) — and shop all Feliway deals here