I ordered the 72" and the 60", with the intention of butting them up next to each other to run the length of the room.  The shelves are pre-drilled, but the holes are 21.5" apart. They are never going to hit a stud. Since this is my daughter's bedroom, and a shelf potentially ripping out of the wall is not an option, it HAS to go into studs. Which means I need to fill all those pre-drilled holes and re-drill in more appropriate spots, and then repaint the shelf to hide my filled holes. The shelf is supposedly made of "manufactured wood."  It feels a bit plasticky, so I'm praying I can drill through it okay. So much for my great value shelves that claim to install in 15 minutes.