The fit of these goggles are perfect when following the measurement guidelines established by the company. My 8 1/2 year old German Shepherd adapted to them in one day. I followed the recommendations and had fed her dinner while she was wearing them. I repeated the process in the morning and she happily wore them for a couple hours after. We hang them by the patio door and put them on her any time she goes out. She always returns still wearing them.
Thank you for creating a much needed product. I am considering getting them for my other shepherds to prevent pannus.