On a duffel bag, the best place to attach a luggage tag is to one of the permanent, heavy-duty metal rings where the shoulder strap connects to the bag's body. Avoid attaching it to the zipper pulls, as these are weak points that can snap off during the rough handling of the airport’s sorting system. If your duffel does not have metal rings, the next best option is the main carrying handle that is sewn directly into the bag's frame. For maximum security, use a tag with a reinforced steel cable or a sturdy leather strap rather than the cheap plastic loops provided by airlines. Additionally, it is a "pro traveler" tip to place a second ID tag or a business card inside an interior pocket of the duffel; if the external tag is torn off in the conveyor belts, airline staff can still identify the owner by opening the bag. For soft-sided duffels, also consider using a brightly colored "handle wrap" or a unique ribbon to help distinguish your bag on the carousel, as many black duffels look identical from a distance.