The Nite Ize NiteDawg is an adjustable dog collar with built-in LED lights, so your dog can be seen on evening walks and in the dark. This extra-small size fits necks from about 20 cm to 30 cm (8" to 12") and has neon yellow webbing with red LEDs, according to the maker's pack. The collar is used like a normal buckle collar and the lights are switched on and off at the battery module. It is a good choice for small dogs and puppies that are walked early in the morning or after dark. The battery type and run time are not listed in the sources we found, so check the pack.