["brand new and high quality Features: [Cold and hot dual purpose]: This product not only has the function of heat preservation, but also has the function of rapid cooling, achieving a dual purpose. Semiconductor refrigeration chip, low power consumption, long-lasting durability, improve heat preservation / cold preservation speed. [Easy Operation]: The device has two for touch buttons, namely cooling and heat preservation, one-button start [USB power supply]: USB power supply can be connected to a suitable power supply, notebook, charger, convenient and fast. [Waterproof]: High-quality ABS engineering plastic for shell, anti-leakage, safe and secure. [Cup type]: Suitable for most flat-bottomed cups and beverage fillings on the market, support cans, ceramic cups, glass cups, stainless steel cups, etc. (Note: Plastic cups, double-layer cups, thickened bottom cups and flat bottoms are not suitable Pot. The function of this product is to keep warm and constant temperature. It cannot be used to boil water) Specification: 1. Working voltage: USB +5 V 2. Electric current: 5V 0.8~1.3A 3. Operating current 0.6-.75 Security 4. Operating temperature: -20 degrees Celsius to 45 degrees Celsius; 5. Dimensions (length x width x high): 13.8cm X 8.9cm X 3.7cm (not including power cord) 6. Applicable cup type: metal cup with max. 75mm diameter 7. Highest temperature on matal plate surface: 60 celsius, difference 5% 8. Lowest temperature on matal plate surface: 15 celsius, difference 5%(25 Celsius degree test environment temperature) NOTE: 1. This product is only suitable for PC, with USB interface. 2. Use the product gently to avoid severe vibration, so as not to affect product performance. 3. This product must be directly inserted in the computer USB interface. Using relevant USB hub and other related auxiliary equipment will reduce performance or damage the equipment. 4. When it is warming ,must put container on matal plate to avoid damaging this item itself 5. This product is no match for the houshold appliances as it is powered by the USB interface. Package includes(without retail package): 1 x Coffee Mug Warmer"]