The ZDX 21” International Carry-On Wheeled Duffle offers the best of everything, combining the roominess of a duffle with the convenience of a wheeled carry-on. It boasts our patented Outsider® handle for a flat, roomier interior, perfect for bulky sports gear or parkas, plus an easy-access pocket to hold items for security checkpoints and an outside battery pocket so you can keep charging your phone as you roll along to your weekend adventure.