This is a stackable holder meant to organize 3.5" hard disk drives. It is very quick to print, uses little filament, and helps me organize my backup and archive drives. The drives are just stacked on to of each other. No need to fasten them, the slanted edges of the holder and the weight of the drives suffice to stabilize the stack.

The design was strongly inspired by this one, but I needed it to be shorter so the drives would fit the docking bay.