This proprietary technology, developed and field tested by a Ph.D. and author of several books, will gently ward off deer keeping them at a safe distance from those expensive plants and shrubs. Keeping deer at a safe distance from our plantings is one of the more difficult obstacles that Mother Nature has cast upon us. That, coupled with the fact that deer carry ticks that spread Lyme disease and other diseases that afflict humans, is the perfect reason for Deer Chaser™.Engineered with special sound level and light intensity to scare away deer but remain unobtrusive to humansDeveloped by a PhD plant scientist and found to be extremely effective in tests performed by Big Game Biologist with New York state''s Department of Environmental ConservationWide angle of sensitivity, up to 25 feet from the unit, can protect an area or redirect deers'' path of travel away from garden plantsEffective year ''round; simple battery operation means that you do not need to bring either water or electricity to area that you need to protect