ABS+PC material, durable and lighter hard shell, features textured finish to prevent against scratches. The beveled edge design on the upper part increases toughness for the luggage. 20inch and 24inch luggage is perfect for business and personal travel, 28in is expandable add 15% to the scalable space. Sturdy ergonomic aluminum telescoping handle system provides fluent and smooth experience. The unique shaped multi-directional silent wheels will not make any noise when being rotated and it’s more durable in structure. TSA lock which allows only TSA agents to inspect your bags without damaging the lock Worldwide 2 year warranty.Please note that ONLY 28in is Expandable, adding 15%to the scalable space.