Waterproof, impact resistant, and visible up to 3 miles away, this is the light that Danish search-and-rescue teams rely on to keep their dogs visible in dark and dangerous conditions. The low-profile LED fastens anywhere on your dog's collar via a clip or hook-and-loop strap (both included), and can be switched on simply by rotating the lens. Steady and flashing modes. Waterproof to 330 feet. In red, amber, clear. 100,000-hour bulb, 250-hour battery life. Weighs less than 1 oz.