Waterproof led display - waterproof led display that can be completely submerged in water. Just touch the led screen and the temperature of the liquid will show on the led screen. You do not have to test the temperature with your mouth or risk getting burned. Durable temperature control - the vacuum of the cups block heat transfer. Our products hold liquid above 42 ° c for up to 6 hours and liquid cooling below 10 ° c for up to 5 hours. Safe&healthy material - the inner wall is made of 304 grade food grade stainless steel and the outer case is made of high quality 201 stainless steel. It has been approved for your drinking needs. Ultra capacity battery - lithium battery with large capacity, screen turns off automatically when not in use and can reach a battery life of 2 years. Don't need to worry about battery rechange issue daily. Wide applications - with the state-of-the-art double-wall vacuum technology, this mug is stylish and durable. Whether you are traveling, at home, in the office or outdoor - the ideal companion. Simple and practical, it is the best christmas gift for friends, family. What's in the box 1 x Stainless Steel Vacuum LED Temperature Display Smart Water Cup - Black