Specifications: Deer warning device is friendly for animals. Can emit ultrasonic automatically day or night at speeds above 35 MPH and will warn deer up to 1/4 mile away. The purpose of the deer whistles is to stop the deer from running in front of your vehicle. We upgraded the normal double-back sticky tape to adhesive tape which is pretty sturdy, they will stay in place even through a professional car wash. And each whistle comes with an additional adhesive pad for replacement. Made of premium plastic which can resist all weather, even stay at outside extreme heat or below freezing, the device can work well. Just peel off the tape cover and stick the device to your bumper or grille. And the whistles can conveniently be removed from base for wash your car. Two deer warning whistles are recommended per vehicle. Type: Deer Warning Whistle Material: ABS Quantity: 2Pcs Features: Easy to Install, Warning Deers, Animal Repeller, Ultrasonic Size: 5cm x 2.3cm x 2cm/1.97" x 0.9" x 0.79" (Approx.) Notes: Due to the light and screen setting difference, the color of item may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 2 x Deer Warning Whistle Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.