The Guardian Hunting Dog Light is designed with your dog's safety in mind. The sturdy, water-proof and crush-proof design ensures your dog will be visible to other hunters. This high visibility light can be seen up to 3 miles away. Perfect for extreme weather conditions and temperatures. The heavy duty attachment is perfect for 1" to 1.5" leashes and collars and will stay in place across all terrain. Steady and blinking light modes are changed simply by flipping the battery over. Twist the light housing to turn on or off.