When sourcing duffel bags with wheels, prioritize high-denier fabrics (e.g., 1680D ballistic nylon or 900D polyester) for superior tear resistance. Ensure the telescopic handle is made of aircraft-grade aluminum with a multi-stage locking mechanism. For the wheels, heavy-duty polyurethane (PU) or rubber wheels with sealed bearings are essential to ensure smooth movement and durability across various terrains. Additionally, verify that the zippers are YKK or equivalent high-strength brands to prevent bursting under pressure.