It is very convenient because it is possible to use a single car when storing a small baggage and connect it in case of a big cargo.
When not in use I think that it is well done that there is no such thing that it does not fall off because the depression of the tire is made in the loading platform so that it can be stacked and stored.
It is easy to use as a trolley body because it is light and easy to hold. However, although four tires are attached, there is a tire whose axis does not turn only in one place, so I was in trouble because it can not be bent when moving it at a right angle. Especially when connecting dolly, it is also hard to know which tire is fixed.