20 inch: Usually boarding, suitable for 1-3 days of excursions, such as business trips, surrounding tours, etc. It is relatively small in size, easy to carry and can be easily placed on the plane's luggage rack.
24 inch: It is a relatively common size, suitable for 3-7 days of travel. It can hold more clothes and daily necessities, but generally cannot board the plane directly and needs to go through the check-in procedures.
26 inch: Suitable for 7-10 days long-distance travel, with a large capacity, which can meet the needs of longer travel. However, it is relatively large in size and weight, so it may be inconvenient to carry.
28 inches and above: suitable for families traveling, studying abroad, etc., where you need to carry a large number of items. The suitcase of this size is very large in capacity, but it is also very heavy, making it more laborious to carry.