Packaging Includes:Includes 2*Large deer whistles: one ultrasonic whistle (whistle with a hole in the tip) and one wind whistle (whistle with a closed hole in the tip); 2*Small deer whistles: one ultrasonic whistle (whistle with a hole in the tip) and one wind whistle (whistle with a closed hole in the tip) Design:Waterproof construction and adhesive backing make installation quick and simple - just peel and stick the whistles where you want them on your vehicle. High Material:Made of ABS plastic, it is rugged and durable and can be used in harsh weather conditions. Application:These whistles emit a high-pitched sound at speeds over 35 mph that alerts deer to oncoming vehicles, helping to prevent collisions.Operates day and night. Car deer alarm for all cars, SUVs, trucks, motorcycles, ATVs and more. Safety: Proven effective at deterring deer, these whistles help protect you, your passengers, and local wildlife from the dangers of vehicle collisions.