I have hunting dogs so this is an invaluable tool to keep them safe if they should cross a road while trailing. However the design changed. Where as the loop that went through the collars use to be solid they are now open on both ends. I have never lost one of the old designed ones. In the last few months I have lost two and my friend has lost a couple. The open end ones are no good. So my 3 star rating. They must now be zip tied on the collar to prevent loss.