Shelf hook - keyhole-slot mounting

I got nice shelving unit with keyhole-slot mounting system on adjustable steel shelving uprights. 2 bows were too big to fin on a shelf so I made hooks My keyholes are about 11 mm upper part diameter, 5.5 mm for lower. Keyholes are spaced 32.5 mm apart. Use OpenScad script to fit it to your mounts - width of hook is customizable as well. I had a couple of prints fail when small mushroom fixing detached from bed so I added tiny skirting to it. It is easy to remove though you do not even need to remove it. Hook is made to be light yet strong - it easily holds 8 kg kettle-bell.