I bought 7 series collars for muy dogs. They came from china and they don't work. My dogs still itch with fleas. I tried with no success to contact the company who has a hotmail account *******@hotmail.com but was never contacted back. I tried the phone number 1 *******177 with no message or answer. They also have the same under petsrepair.com.
Do not buy from them and call the contact number first and make sure the email is not a hotmail address. It sounded to good to be true and it was.