3-Day Harvest has been scientifically formulated and field-tested under real hunting conditions to give hunters and wild game managers a truly remarkable system for attracting deer. It uses the animal's most powerful sense, smell, to attract deer like a magnet. And it keeps them coming back for more with its highly-palatable, great-tasting formula. See for yourself why deer are in the area because of the irresistible smell and great taste. 3.7 gallons.