A
unit load device (
ULD) is a
pallet or
container used to load luggage, freight, and mail on
wide-body aircraft and specific
narrow-body aircraft. It allows a large quantity of cargo to be bundled into a single unit. Since this leads to fewer units to load, it saves ground crews time and effort and helps prevent delayed flights. Each ULD has its own packing list (or
manifest) so that its contents can be tracked.