The concept for this box comes from a gentleman named Ross Arnold. All the details and my thoughts on the design process on my website.
The box has 5 drawers, but the bottom one is built upside down. A brass pin slides out the bottom of the drawer into a hole in the case locking it in place when the box is right side up. Flip the box over, the pin retracts and the drawer opens right side up. The other four drawers can be removed prior to flipping it over to keep them organized