I need to cool my AV receiver, which is in a cabinet with limited vertical space. I want to install a Noctua 120mm fan, but if I simply mount the fan, the hot air will remain trapped inside. With this adapter, I can (hopefully) direct the air straight out of the cabinet.

I printed a Rummikub set I found online – the tiles looked great, but the rack included was too big, especially the base, which took up too much space on the table. Also, the levels were too close together, so the tiles would block each other. After 5 design iterations, I came up with this compact and practical version: better spacing between levels, stable, and with a much smaller footprint. Hope it’s useful to others too!