FELIWAY MultiCat Refill for Cats #1 brand used and recommended by veterinarians Clinically proven to work. Can see results within 7 days. 70% reduction in conflict in 3 weeks Drug-free solution that helps reduce conflict between cats living together. It may help decrease fighting, chasing, blocking and staring MultiCat Refill includes one vial that lasts up to 30 days (diffuser head not included, sold separately) 100% satisfaction guarantee