Square trays make it easier to dry more strips of jerky flat and evenly. Square shape provides over 40-percent more drying space than comparable round dehydrators. It increases the capacity of drying space by 200 more square inches. Patented Converge-Flow drying action ensures fast, even heat distribution. No need to rotate trays. This Add-A-Tray fits the Nesco FD-80 and FD-80A Square Food Dehydrator (sold separately).