This is a two-piece (top & bottom) housing for the Libre AML-S905X-CC "Le Potato" single board computer. There are two versions of the top housing posted. One which has a long rectangular opening in the top for access to the 40 pin header for GPIO applications and another without this access (shown). To assemble, you need qty(8) M3 hex nuts that get pressed into the openings on the bottom, qty(4) M3 x 6mm long socket head cap screws to mount the board to the bottom housing and qty(4) M3 x 16mm long socket head caps screws to fasten the top housing to the bottom. The opening and bolt pattern on top is for a standard 40x40 5v cooling fan (search for Raspberry Pi cooling fan). Additional mounting hardware is needed for the fan (the ones I bought included the mounting hardware).
The author marked this model as their own original creation.