Good product at a great price
I live in North Carolina, had been using Frontline for my cats to prevent fleas, and it wasn't working any longer. Then I tried Revolution and I still had breakthrough fleas.
Finally I tried Activyl and it worked and the cats are completely flea-free. I buy the extra-large dog size and each vial is just enough to treat all four of my cats. So it's very cost effective. I just pour the vial into a glass tube and use a syringe to put it on each cat.
The fleas have started to become resistant to some of the older flea topicals, and Activyl is new enough that it still works. So glad I found it.