It's nice that you don't need tools to assemble these shelves but there are these little plastic things that you have to lock onto the rods to keep the shelf in place. You need them in place on all four rods before you can lower the next shelf and they just pop off sporadically and go flying across the room. Scotch tape was fine for keeping them in place but the initial process was really frustrating. 

They were also smaller than expected but that was my fault for misjudging the measurement.