This vacuum insulated stainless steel tumbler This vacuum insulated stainless steel tumbler is made from 304 stainless steel which is of good quality, food grade and durable. The inner wall is electron-polished without any gaps which makes the tumbler rust-proof and will not leave any taste. It can hold hot and cold drinks for several hours, ensuring that your drink will last longer and keep fresh odor. The stainless steel mug comes with two types of leak-proof lids, one is a sliding lid and the other is a flipping closure lock, which keeps the heat and reduces the spill. All the lids are made of BPA free plastic, so it is safe in daily use. The straw hole on the cup lid that makes it convenient for you to insert a small straw.It is suitable for sports, travel, camping, party, etc,custom