The three cases in this set are matched to airline categories rather than just to inches. The 20-in case measures 12 in by 8.5 in by 22 in, holds 37 L, weighs 4.5 lbs, and is rated as airline standard carry-on, so it is the one that goes in the cabin for a 1 to 4 day trip. The 24-in case measures 18 in by 10 in by 27 in, holds 76 L at 6.5 lbs, and goes as checked baggage for 4 to 7 days, while the 28-in case measures 20 in by 11.5 in by 31 in and opens up to 114 L at 9 lbs for trips of 7 to 9 days. That 114 L is a genuinely large hold case, and it is worth knowing the number before buying rather than guessing from the label. All three are moulded in ABS with a robust hardshell that is scratch-resistant and impact-resistant, so the finish survives baggage handling instead of scuffing on the first trip, and each rolls on 360 degree double spinner wheels that stay silent, smooth, reliable, and flexible under load. Inside, multiple compartments keep belongings tidy and accessible and smooth zippers open and close the case without snagging. A sturdy adjustable telescoping handle sets the towing height, reinforced grab handles take the lift onto a belt or into a boot, and a secure 3-digit lock increases safety. Between trips the nesting design stacks the smaller cases inside the larger, so the 21 lb set stores in the space of one case.