Typically, their internal layout mirrors that of a carry-on trolley, featuring one or two spacious compartments for storing clothing and reducing bulk using special adjustable straps and several pockets, on the front and sides for storing all the essential travel accessories, such as boarding passes or a passport. The lightweight design and ergonomic shoulder straps are another feature not to be overlooked, especially when traveling with children, as they enhance travel comfort. Finally, dimensions are crucial: Ryanair, for example, requires a maximum size of 40x20x25 cm; for other airlines, we recommend checking the updated size requirements on the airline’s website before you leave.