It can be upgraded into a medium storage unit with 8 mallignum root planks. The chest can be used as an additional place for storage besides using your bank. Bring lots of un-noted items with you to raids that you want to store. It is useful to leave some inventory spaces open and to bring a hammer. It is not required to leave some inventory spaces open, since you can drop-switch the planks and hammer around to still build the storage chest, but it does make it a bit easier and safer (since dropped items will be lost forever if you leave the dungeon for whatever reason). You are however able to store less items that way. You can carry some additional items by bringing some equipable items with you. Bringing the looting bag does NOT work in this method.