Welcome to a whole new world of nighttime visibility. Two ultra-bright LEDs send light through an integrated optical fiber to create full-length illumination so bright you need to see it to believe it. Featuring the convenience of rechargeability and easy push-button operation, this collar lights up for more than six hours on a single charge. Nite Ize optical fiber technology transmits light throughout the entire length of the collar without loss of light output and offers both constant glow and flash mode. The high-quality metal belt-buckle style closure is simple to adjust. This highly water-resistant collar is designed for ultimate durability and is available in a variety of sizes to fit large and small dogs.