As one of the most ubiquitous and useful pieces of equipment on a film set, apple boxes are used for anything that needs to be raised up or supported temporarily. They can be used to raise furniture and light stands, for levelling out camera dolly tracks, or to provide seats, stepladders, or workbenches.
This set of Pancake boxes allows for more refined height increases as well as being lighter and more stable to stand on than its big brother.