“This is OK for my smaller cats, but not strong enough for my 20 pound cat. I have to used revolution or another one recommended by my vet. I use the automatic refill of this product. Be careful, they accidentally tripled the refill for a 12 month supply (I have 6 cats) and had a bill over $400. I refused one of the refills and they had the nerve to charge me a restocking fee.”
