This dog-tested light is sturdy, compact, watertight, lightweight, and easy to use. The Beacon securely clips onto all Ruffwear wearable dog gear, runners, hikers, cyclists, kids, and equipment. High-intensity LED creates a halo of red light around dog. Omni-directional, light dispersing lens with multiple blink modes: slow flash, fast flash, and always on. Durable, watertight, low-profile design. Batteries included. Split ring attachment option.