I was not sure which collar to get either for the smallest setter I have ever owned. I have been used to having bigger Ryman/Hemlock dogs that broke 80 lbs. The one I have now is fully grown at 30 lbs. Anyway, was able to open a box of the mini to review what size neck the collar band will cover. I have surmised the stimulation would be nearly the same whether the collar was a mini or standard size and the battery life for the mini would be less. However, I did not call Garmin to verify those aspects before I bought the mini. That being said- if I have another athletic 80 lb dog (not obese), I have no doubt the collar will fit him/her. Maybe you can review the collar band of a mini at a retailer for yourself and maybe call Garmin to determine what differences can be attributed to the size of the receiver on the collar.