Features: 1. Protect Animals : Made of ABS plastic, which is durable and waterproof. It can warn deer and other animals that there are vehicles coming in front of them, prevent them from being hit by vehicles, and reduce injuries. 2. How It Works : When your car is driving at 30 miles per hour or faster, the whistle will automatically make a sharp sound, prompting the deer to leave quickly. 3. Compact Dual Structure : The whistle has a dual structure and a single installation. This small whistle is easy to hide and replaces the traditional separate deer warning whistle. 4. Simple Installation : Just tear off the double-sided tape at the bottom and stick the whistle on the front bumper, rearview mirror or any flat place. 5. Wide Range of Applications : Suitable for all brands of cars, trucks and motorcycles. Perfect for sending as a gift for someone who travels a lot in the wild environment. Installation Steps: Step 1: Measure the area in front of the car to ensure that there is enough space to install the deer whistle. The ideal place is in the grill, where the air flow is the most. Step 2: Clean the area and remove any oil, wax or other substances to prevent the deer whistle from sticking. Step 3: Peel off the rubber bottom and stick the whistle on the grill. Check again whether the deer whistle is level with the horizon. Let the deer whistle forward. Notice: Actual color may be slightly different from the image due to different monitor and light effect. Please allow 1-3cm deviation due to manual measurement. Material: ABS Size: about 5 * 4 * 1.2cm/1.97 * 1.57 * 0.47 inches Features: easy to install, not obvious Battery: No Color/Style: As the picture shown Weight: 25g/pair includes: 2 x Automotive Deer Alert Whistles