Traveler's Choice New Luxembourg 2pc Carry-On Hardside Luggage Set (Royal Blue) Lightweight yet extremely durable High Tech Molded hardside provides maximum impact resistance The ABS hard-sided material gives the luggage greater rigidity so that it will not permanently deform when under pressure but instead 'pop' back up into its original shape Internal retractable aluminum dual-tube telescopic handle with push button system 21 in. & 18 in. hard-side rolling carry-ons: Feature 2 recessed in-line skate wheels with aluminum ball bearings for smooth and quiet rolling 18 inch hard-side can be rolled from curb to airline aisle, and it will fit under an airplane seat