Nite Ize brilliantly durable rechargeable NiteHowl LED Safety Necklace is made with a flexible polymer thats illuminated by bright LEDs and can be recharged for hours of nighttime fun and safety. With Disc-O Select, this NiteHowl makes identifying multiple dogs easy with the ability to choose from one of three selectable colors (red, green, blue), plus a unique Disc-O mode that youll have to see to believe. By illuminating the polymer with multiple colors at the same time, Disc-O mode creates a flowing color-blending pattern thats as fun as it is functional. To use the NiteHowl, simply trim the flexible polymer to a custom fit, 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.