I’ve used the Seresto collars on my last 2 dogs and really like them. A fake, though, can be very harmful to the dog so be carefully to buy directly from a vet or reliable source. A Google search can lead to info. on how to tell fake from real. I cheaped-out once and bought on eBay. Luckily I realized it was fake by the markings on the collar before using it on the dog.
