I purchased the light up collars for ours dogs, we live in a rural community and it is dark at night, the light up collars make it easy to see the dogs running and playing at night. Its so fun to watch them dancing in the darkness! Love them so much I bought 2 for my neighbors dogs. The batteries last so long I haven't even had to change them in 2 months. I will buy these for the Whole Town if I have to!