The Charles Viancin Voretex Silicone Ring has raised edges to prevent liquids from boiling over into your stovetop. Unique design fits a variety of pot sizes to match your cooking needs. Central opening allows you to stir your food without worrying about spills. Anti-spill shield prevents food or liquid splattering outside the pot. Serving is simple without worrying about difficult clean-up afterwards. Max temp +428 degrees Fahrenheit, minimum temp -40 degrees Fahrenheit. Microwave and oven safe. Dishwasher safe.