Our brilliantly durable NiteHowl LED Safety Necklace is made with a flexible polymer tube, illuminated by bright LED's, and simply slides over your dog's neck for hours of nighttime fun and safety. To customize the fit of the necklace to your dog, simply trim it with scissors to anywhere between 12" and 27". To activate, give the button on the durable, weather-resistant housing a quick press, and the entire collar lights up a full 360 degrees making your dog clearly visible from all angles. The necklace can be set to either glow or attention-getting flash mode. This pet light necklace comes with easily replaceable 1154 alkaline batteries, so you can reuse it endlessly for all your late night and early morning walks. With a variety of colors available, you can use a different color for each dog in your group for quick identification in the dark.