Vented Glass Lids by Cuchina Safe are Universal flat lids that fit on top of multiple sized bowls, pans, pots and containers. They are made for healthy steaming and cooking in the microwave, on the stove top (not for direct flame or broiler) and in the oven up to 450 degrees Fahrenheit. Glass lids allows moisture to rain back down on the food to stay moist and 3 vents allow for just enough steam to escape to hasten the cooking process. Made of strong, durable Borosilicate glass (heirloom quality, like your grandma used), they won't absorb odors and bacteria like plastic lids, are stain resistant and easy to clean! Home chefs can avoid the health risks associated with using toxic plastics, boil-in-bag, and wraps in the microwave. They also serve as splatter shields or spatter guards to keep appliances clean. No more messy microwave to clean!