I have a Jack Russell Terrier, there is not much hair and it is mostly white, ticks are clearly visible on it. Last summer I found five or six pieces, they crawled on the wool, but they didn’t want to eat the dog - it wasn’t tasty. After 4-5 months of use, the action probably weakened and found one parasite that tried to stick, but also did not want to - it left only a barely noticeable pimple. After that, for reliability, I once more dripped on the withers.
Enough for the entire period from AprSee full review