I use it for 2 years.
There are rails front and rear. In addition we have on the central angles that allow removable support the weight of some racks that are heavy. In addition to 24U was enough to make available at racks!
I tried a lot of flight of any kind before.
For me the report is qualitprix trs good.
What you should know is that this rack is not portable, but for some, unwanted studio is perfect. Trs is robust and resistant.