Save Your Car: Two pairs of car whistles, with wind and ultrasonic signals at speeds up to 35 mph in a collaborative environment, which will effectively dodge, preventing any further damage to your lost car. hese will work above 35 mph. Easy to install and remove: The bottom of the whistle is a strong adhesive strip, which can be installed on the front bumper or roof of a vehicle with good air circulation. It will not fall off even when driving in rain or snow. You can also tighten the base with two small screws. They can be removed from the base for cleaning or car washing. SAFETY GIFT FOR DRIVER: This is a defensive car accessory for drivers living in the wild. The siren produces ultrasonic frequencies and wind warnings, thereby reducing vehicle collisions. Note:1. Please allow a little error due to manual measurement. Please make sure you don't mind before bidding.2. The color may vary due to different monitors, please understand. Note:Hello, please pay attention to your delivery address when purchasing products. If your receiving information (such as: name, street, house number, doorbell/email without name, etc. is incorrect, the order will not be delivered correctly.)