This Mug with a lid is made of a durable stoneware material and is oven safe (preheated oven);Soup Mugs Microwave Safe, dishwasher, refrigerator, freezer, & resists chipping & cracking;Plastic lids are BPA free, top-rack dishwasher safe & refrigerator and microwave safe;Great for soup, coffee, tea, chili, oatmeal, hot cocoa and more;Mug Measures 6 x 4 3/4 x 4 and carries a 1 Year Limited Warranty. Lids carry a 2 Year Limited Warranty.