I just wanted to add that the vet that I used to take my cats to was the one that suggested that I buy the large dog advantage because the ingredients are the same as the cat advantage. He did this to help save me money. I only had 4 cats back then. Since I live in CA, I have to treat my cats year round and so far so good. You can also probably get free syringes from your vet or any other vet office when you buy the advantage from them. The numbers will eventually wear off of the syringes so I use either masking tape or surgical tape to mark off the right amount that is needed. I also have an empty plastic test tube with a lid that I squeeze the advantage into so then I can measure it out and save whatever is left over for next time. Good luck.