In order to keep drinks hot or cold, to take to the office, school or picnic, or while training or moving, there is a wide range of designs, styles and colors from which to choose a thermos at a good price.
Internally it can be of glass, stainless steel, copper, foam and/or thermoplastic without BPA under a double wall design with coating, vacuum sealing and silicone gasket to keep the temperature as long as possible. Externally a thermal glass is usually cylindrical in shape, in metal, plastic or rubber, and should have an ergonomic and stylized design for better and comfortable grip.
A thermos is formed by the main vessel and a cap, which is to be hermetic, with anti-drip system and easily open/close option. This cover has a screw or pressure closure system and has a small hole that serves as a landfill, which must be closed tightly with a mini plug, or better yet, have an articulated button with locking system.
Some models include a handle, which can be folded or not, for easy transportation. It is advisable to consider that the thermos is suitable for use in microwave, dishwasher or freezer for convenience of use.
When checking the available models to acquire a new thermos, do not forget to examine the thermal insulation and the ability to maintain the temperature properly.
The thermoses tend to come in three basic materials as plastic, steel, ceramics or glass. According to some tests, the thermos for plastic coffee cannot retain the heat for more than an hour, while the ceramic ones do not even 30 minutes. So I do not recommend ceramic or plastic, as it removes all logic of having a coffee thermos. In addition to this, they break easily, so in my tests I have left these two categories out. Besides the plastic has health hazard as well.
Occasionally, I find some models of thermoses of steel on the outside and a ceramic or glass inside. This option accustoms to be better to the above, especially for those people who really feel a change of taste when they drink from a steel interior. Some prefer steel interiors. Being more specific, steel interior is easier to clean and to get the taste of coffee in case you want to use it for something more like tea or water. Regardless of how sophisticated you have the palate, many people agree that a fully sealed and airtight thermos is the best choice. It is the best material that retains and breaks less if you make a comparison with other material, so it is a win-win situation for you.