The Tool Box, added by IndustrialCraft, is a box for the handy-miner to keep their tools in. When closed (looks like tools are spilling out of it in the default image) it can be right clicked to "open" it.
When opened, it will release the tools it contains into your hotbar or inventory. To open it, simply right click while holding it.
When opened, if you close it (right click while holding) it will take in all the items in your hotbar for storage until opened again.
Tool boxes are known to be pretty buggy.
Using the Tool Box while on a ladder will crash your game. You may never get the stuff back, that it stores for you. Trying to put 8 tools in the box will crash the game as well and you will not be able to reload the world. If you are able to reload the world and the hotbar is cleared then you'll have a duplication glitch.
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