They come with is a lid to which is fitted a valve which allows steam within it to escape through. In Japan the most famous manufacturer of the items is a firm called Zojirushi. The Oster 4722 rice cooker can make as much as ten cups of cooked rice at a time. I discovered a variety of versions that Zojirushi advertised as stainless steel vacuum bottles on their website. For much more tender rice, increase water and simmer longer.