The nominal volume of a thermos is the maximum amount of contents that it can be guaranteed to contain.
This parameter is directly related to the type (see above). So, a capacity
of up to 500 mL is quite normal for a thermo mug, a flask or a baby thermos, but it is considered small for a classic thermos, and even more so a jug or a thermos for food. The
"500 to 1000 mL" category includes most traditional and food models; for mugs, flasks and children's thermoses, this is actually the maximum volume. Among the jugs there are many more capacious options —
from 1000 to 1500 mL. A volume
of 1500 to 2000 mL is considered quite large, and the most solid models can hold
more than 2 liters.
Anyway, a large volume allows you to hold more drink or food, but the downside of this is an increase in the size, weight and price of the thermos itself. Therefore, when choosing, you should not chase the maximum capacity, but proceed from real needs. For example, a model of 400 – 500 mL is quite enough for two cups of coffee, and for tea drinking at a halt for 3 – 4 people, it is advisable to have a model of at least 1000 mL. More detailed selection recommendations can be found in special sources; especially they will be useful to those who choose a thermos for long-distance hiking trips.
The presence
of a spoon in the scope of delivery of a thermos. This function is usually found in models designed for food storage (see "Type"); the purchase of such a kit will save you from having to look for a spoon separately. In addition, set spoons are sometimes multi-purpose camping cutlery (for example, a combination of a spoon and fork) and themselves can be more convenient than usual ones, often equipped with thermos mounts, etc. However, there are different opinions about the convenience of the entire thermos + spoon set. Therefore, if you are considering such an option, it makes sense to clarify the design features of the spoon, its attachment, etc. and, based on specific data, determine whether the kit will be more convenient than a regular thermos.
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.
