A collapsible sink — a wide, shallow basin that folds flat when you are finished.

A bucket is deep and narrow. A sink is wide and shallow, which is the shape you want when the thing you are washing is a twelve-inch skillet or a stack of plates.

Set it on a camp table, fill it from the water container, wash, and tip it out away from camp. Folds down for the drive home.

Most camp kitchens end up with both a bucket and a sink, because they do different jobs.