I ordered 3 Seresto collars from Singpet, being attracted by the low price. The collars was completely ineffective. My dogs, after wearing the collars for at least a month are scratching more than they were before I put the collars on! Obviously, I can't have any confidence in the Heartgard based on the collar experience. I have replaced both of these items and am out over $100.00. I emailed Singpet and someone from United pet world (a sister company) questioning the authenticity of the product and was told I should take my dogs to the vet because the "scratching could be caused by something else" There scratching because they have FLEAS!
I was also told all products sold on their website are genuine but I truly have my doubts.
Since I have used this product before and had the container from the Seresto I purchase from my vet and noticed at the end of the O tm (trademark) on it but not on the 3 that I purchased from Singpet! So genuine... I'm not so sure.
Any reputable supplier would have offered to refund your money. Not this company!