Durable and high quality stainless steel, vacuum insulation with excellent heat retention that keeps soup and main bowls hot or cold. 4 inner bowls are microwaveable and remain nicely contained in jar with a clip-on lid; 41 oz total capacity. Includes easy-to-carry bag that holds the jar and a forked Spoon with cover. Washable jar with nonstick Coated interior. Made of BPA-free plastic and stainless steel.