Nice collar but don't work if cold

This is a nice collar. Made of a sturdy nylon. The leash clip is very strong and durable. The brightness of the collar is pretty good however the collar will lose brightness if it is cold outside and then just not work. I live in a colder state and it was about 25 degrees and the collar only worked outside for about 20 minutes before we couldn't see the dog any longer. These are fabulous to have when outside to keep track of where the dogs are. Easy to locate when the collar is illuminated.