I used to swear by this stuff.  Used according to directions, it killed fleas and cleared up an infestation right away, and its residual effects lasted for nearly a year.  It was a great product.  As a matter of fact, I haven't had another infestation (until now) for many years.  So, when some feral cats got in my garage and decided to bring their fleas along, I brought fleas inside to my indoor-only cats.  After treating my cats with Revolution, I decided to use a "new" old can of this that had been sitting in the closet for years.  That can produced a little bit of spray, but mostly squirted out foamy stuff that would not dry, so several hours later, I had to swish it into the carpet with a broom.  Also, it left stain marks where the foam was.  To top it off, I did not notice any difference in the flea population.  I assumed the age of the product had something to do with it, so I ordered a new can - this one that I am reviewing.  This brand new can produced a tiny bit of spray, but mostly foam (and yes, I shook it well before and during use).  Instead of using it on my carpet indoors (just in case this can foamed also), I tested it out in the garage, using it on the throw rugs/mats in the garage, as well as the bedding I put out there for one of the feral cats who has decided to stay in the garage several nights a week (via a kitty door).  After 4 hours, the foam, which pretty much covered everything I sprayed, was still wet and gloppy, so I had to swish it in with a broom so it would dry and the cat could come back in without being poisoned by it.  It left white stain spots every single place the foam was.  Worse, it did not seem to have any effect on the fleas.  I waited two weeks and did it again, and I do think it has helped some, so that's why I am giving it two stars instead of one star.  But I will now try a different product, and I'm thinking of trying Adams Plus Flea & Tick Carpet Spray.  I used Adams spray many, many years ago, and had good results with it, but then my local pet store recommended the Zodiac, which I found to be superior to Adams at the time.  But I'm not willing to have non-drying, staining globs of foam all over the place that have to be swished in with a broom or brush...Too much trouble, and too dangerous for my cats.
I used to swear by this stuff. Used according to directions, it killed fleas and cleared up an infestation right away, and its residual effects lasted for nearly a year. It was a great product. As a matter of fact, I haven't had another infestation (until now) for many years. So, when some feral cats got in my garage and decided to bring their fleas along, I brought fleas inside to my indoor-only cats. After treating my cats with Revolution, I decided to use a "new" old can of this that had been sitting in the closet for years. That can produced a little bit of spray, but mostly squirted out foamy stuff that would not dry, so several hours later, I had to swish it into the carpet with a broom. Also, it left stain marks where the foam was. To top it off, I did not notice any difference in the flea population. I assumed the age of the product had something to do with it, so I ordered a new can - this one that I am reviewing. This brand new can produced a tiny bit of spray, but mostly foam (and yes, I shook it well before and during use). Instead of using it on my carpet indoors (just in case this can foamed also), I tested it out in the garage, using it on the throw rugs/mats in the garage, as well as the bedding I put out there for one of the feral cats who has decided to stay in the garage several nights a week (via a kitty door). After 4 hours, the foam, which pretty much covered everything I sprayed, was still wet and gloppy, so I had to swish it in with a broom so it would dry and the cat could come back in without being poisoned by it. It left white stain spots every single place the foam was. Worse, it did not seem to have any effect on the fleas. I waited two weeks and did it again, and I do think it has helped some, so that's why I am giving it two stars instead of one star. But I will now try a different product, and I'm thinking of trying Adams Plus Flea & Tick Carpet Spray. I used Adams spray many, many years ago, and had good results with it, but then my local pet store recommended the Zodiac, which I found to be superior to Adams at the time. But I'm not willing to have non-drying, staining globs of foam all over the place that have to be swished in with a broom or brush... Too much trouble, and too dangerous for my cats.