Here's what we drag with us as we tour this big world of ours.
We have two of these, one in blue and one in yellow. Of all the flights we've taken, we've never seen another one of these popping out on the luggage carousel at the airport.
We keep the weight of each one to between 15 and 19 kilograms (33 to 42 pounds). They seem to handle that just fine (the trick is to keep them under 20 kilos, which is the cut-off point for "heavy" bag charges at many airlines). Empty, each one weighs just over 3.5 kilograms.