General description This set includes 4 deer whistles that use wind to emit ultrasonic waves to repel deer, wild boars, and other animals, requiring no batteries or maintenance. The car deer whistle is made of high-quality plastic, ensuring strength, durability, and reusability. It emits ultrasonic waves that are harmless to humans but annoying to animals, providing an ethical and safe solution to prevent vehicle damage. Technical specifications Material: High-quality plastic Effective range: Works within a quarter-mile radius Speed requirement: Effective at speeds of 35 miles per hour and above Usage Scares away deer, bears, cats, dogs, and other animals while driving Helps prevent animals from suddenly crossing the road, reducing the risk of accidents Other information Manual measurement may allow an error of 1-3 cm Color differences may occur due to lighting and display variations