Katzco Save A Deer Whistle - Ultra Sonic Noise Inaudible for Human Only for Deer's- Begins Working at 35 MPH- Powered by Wind Energy, Non-Electric- Value 2-Pack- Avoids Deer Collisions for Car ULTRA SONIC SOUND- those deer whistlers ultra-sonic sound is not audio able to human or pets inside the car, alerts animals up to a  mile ahead, which makes it the exact item to keep away deers but you should stay comfortable inside. EASY USE AND INSTALLING- just peel off the cover and stick it to your bumper or grill, keys included for easy removal, automatically activated as your vehicle travels by wind energy - no wiring or batteries or any electrical use. VALAUBLE 2 PACK- we provide you with the most valuable 2 pack long lasting non-electrical deer whistler for a spare or just for your second car. NEVER AGAIN- buy this high quality deer whistle and never again experience a Deer be suddenly startled and bolt in front of your vehicle with a high damage auto collision. 100% SATISFACTION GUARANTEE- try it,it's totally risk free! If for any reason you decide you dont like it, just send a simple email and get a full refund! Absolutely o questions asked, so you have nothing to lose, click add to cart now!