Electronic Smart Food Dome and Cake Plate - Auto-Vacuum Seals With the Push of a Button - and Reseals Whenever Air Comes In Keeps your food fresher- longer! Vacuums air out with the touch if a button and automatically keeps air out Protects food from pests Battery operated- 2 AA or C (C is recommended for longer life) Perfect for cakes, bread, cookies, desserts, and more