Corningware 20-Ounce Oven Safe Meal Mug with Vented Lid, French (Pack of 2) Glass and plastic lids make cooking, serving, and storing easy and convenient Durable stoneware material designed for use in oven, microwave, refrigerator, and freezer Corningware material resists chipping and cracking Non-porous surface does not absorb food odors, flavors, or stains Includes 2 CorningWare French White 20-Ounce Mug