This feature means that the thermos is equipped with
two cups or bowls at once (depending on the type, see above).
Many modern thermoses are equipped with a drinking cup or a food bowl; in the stowed position, such a container usually plays the role of a lid. In some models of cups / bowls, there can be two at once, which is useful if the thermos is used not only for yourself: you do not have to carry additional dishes with you separately.
The special
handle for convenience of carrying of a thermos. The design of such a handle can be different: for example, in ordinary thermoses and thermo mugs (see "Type") it is usually installed on the side, in food thermoses and jugs — from above (and is made collapsible). The handle can be a structural element of both the thermos itself and its cover (see below). In addition, the small carrying strap that some models are equipped with is also considered a handle in this case (but the shoulder strap does not count, see below).
Anyway, holding a thermos by the handle is usually more convenient and safer than by the smooth body, especially when it comes to a large-capacity model.