WATERPROOF LED DISPLAY: Waterproof LED display that can be completely submerged in water. Just touch the LED display and the liquid temperature will show on the LED display. It is not necessary to test the temperature with your mouth or you risk burning yourself. (If the product is dyed within one year. please contact us as soon as possible) KEEP WARM AND COLD LONG TERM: Vacuum cups and mugs can block heat transfer. Our products retain liquid heat for up to 6 hours above 42 C and liquid cooling for up to 5 hours below 10 C. That's longer than other vacuum bottles. A filter is also included which can block the tea. the fruits. ice cubes. etc while drinking. SR AND HEALTHY MATERIAL: The inner wall is food grade 304 stainless steel and the outer case is high quality 201 stainless steel. It has been FDA approved for your drinking needs. Of course. 100% BPA free. (Cut: 6.5cm*6.5cm*23.3cm) ULTRA CAPACITY BATTERY: Large capacity lithium battery. the screen turns off automatically when not in use and can last for 2 years. You don't have to worry about the problem of changing batteries every day. WIDE APPLICATIONS: Using state-of-the-art double-walled vacuum technology. this mug is stylish and durable. Whether you're on the go. the House. in the office or outdoors - the ideal companion. Simple and practical. it is the best Christmas gift for friends. the family.