The collar works well and has a good light. My dog has a very short rusty red coat and completely disappears in the park at night. This collar is just what we needed.
I wish there were more sizes; my dog is at the smaller end of 'large' and by the time the collar is adjusted, only half of it lights up. I can see where she is unless she's standing just the wrong way, but as soon as I call her and she moves, then the light shows again.