Each upright has four slats, with each having a set of evenly-spaced holes along their entire length. Each hole has a counterbore, some on outer facing side the slat, and some on the inner facing side:
It took me a bit of head
I think one of the most eye-catching details of the Albini bookcase are the tapered blocks that form the feet and mounting points for the 4 vertical slats per upright (I'm going to call the top ones feet, too.) and their wide round pressure pads.
Our family includes a couple house cats. We also foster kittens for a local shelter to get them socialized prior to adoption. So it's not uncommon for there to be 4 cats in the house at any given time. While the kittens are getting acclimated to t