A box with four stepped sliders arranged around a central knurled wheel, also stepped. The lid is held in place by four latches, one in each side. So, how does it open? The wheel has to be turned to a certain position, and pushed in one direction, which will allow the release two of the four latches holding the lid in place. Then the wheel has to be turned to another position, and pushed in another direction to allow the release the last two latches. Now the lid can be lifted off. The second two latches cannot be released until the first two, even if you find the second wheel position before the first. All the moving parts are contained within the lid. This box is made from 1/8" birch plywood.
Outside dimensions: 5 1/2" length, 5 1/2" width, 3 1/8" depth
Inside dimensions: 4 3/4" length, 4 3/4" width, 2 1/4" depth