Drying is a method of food preservation that has been practiced since ancient times. It works by removing water from the food which inhibits the growth of microorganisms. Water is ususally removed by heat and evaporation with proprer water vapor displacement to allow food to stay dry. Bacteria, yeasts and molds need the water in the food to grow and drying effectively prevents them from surviving in food. - Clear plastic drying trays mean you can check on your food while its drying. - 5 seperate stackable trays means 5 different kinds of your favorite snacks. - Removable trays for easy cleaning and better storage purpose. Dishwasher safe. - Proper air flow helps allow for an even distribution of heat to all trays. - Lighted easy on and off switch. - Adjust the temperature to achieve the perfect consistency for your dehydrated foods.