We adopted a rescue dog. From the very beginning the dog could not function with the collar. Even a trainer was unsuccessful. I called the company to return it and was told unable to return a used item. Do not buy any collars from them. Only buy from Sportdog as they have a 45-day return policy and make the collars so Sit Means Sit may place their name on them. User's recommendation: Buyer Beware...No Return Policy.