So it is supposed to be a 4 unit rack, but... On top there are this pole that holds it together, it is in a way of putting a 1st unit... But, i just got rid off the pole and it is holding together by the unit, so no problem there, unless you want to change units often. 2nd and 3rd unit, ok, BUT in 4th unit, that is in bottom, you can not putt anything that's deeper then few cm... So, not a full 4 unit stand, BUT, it is quite sturdy and really cheap... So basically, it is a 3 unit rack for few euros.