Map Editor Chest items [HELP]

The chest zee Treasure when opened will give you a pirate hat in Napoleonic Wars. Now I believe I have seen other items that can be taken out of chest before. But I'm not sure how to make it so. Is there a variable that must be set, to allow a specific item to spawn inside a treasure chest. I'm stuck on this please help.

I would love to know the answer to this as well. I'd also be curious to know if you can have multiple chests that give out different items.