Review on CEVA Animal Health MultiCat Diffuser Cats by Dawn Wright

. This is enough for 60 days if you only need to use 1. You actually get 2 starter kits that last 30 days each. I was under the impression that I received 2 starter kits with a 60 day supply of each kit. It's not a refill if you need to use it to get started. Refueling occurs after the starter has left. If the diffuser lasts 6 months, you only need one. Then 1 glass is the appetizer and the second glass is the dressing. But that assumes you have less than 700 square feet, then you'll be fine within 60 days. You still don't need 2 diffusers. I can't tell you if it still works and today it's only 1 day old. The packaging says it can take up to 3 weeks. I have had 2 problem cats sniffing the cap, maybe they are sniffing more concentrated and behaving earlier.