This item can be used for quests to save inventory space. Every time you complete a game of Mobilising Armies, the kit replaces any used or banked items. If you have a Quest kit (basic) or Quest kit (medium) when buying the Quest kit (advanced) the price will be reduced.
You can get free supplies from the Quest Kit. If you open a new quest kit and remove any of the items that are in the kit, you can then bank the item(s) and then play 1 game of Mobilising Armies and the kit will regenerate any items removed.
With the introduction of the tool belt, this item has become less useful as many of the tools it hold could be placed on the tool belt instead.