Thermos can be divided into three categories: 1. fine mouth type. Also commonly known as thermos. The diameter of the mouth is small and the insulation performance is good. Mainly used for boiling hot water, hot Chinese herbal juice, hot drinks and cold drinks. 2. large mouth type. Also commonly known as ice bottles, the mouth is large in diameter and the items are easy to pick and place. It mainly contains ice cubes, sorbet, cold drinks with containers, iced pharmacy, liquid gas, anti-fermentation substances, etc. It can also hold hot food and hot drinks with containers. 3. cup type. Also commonly referred to as a thermos cup, the mouth is large in diameter and small in capacity, and it is mainly used to reduce the influence of ambient temperature on the contents in a short time.