The Thon Rack Panels are great value, the quality is good, the price is low. They are a very practical for changing the configuration of your rack. I use only two screws in each panel (diametrically opposed corners), four screws are not needed and it is quicker to changing the setup with only two. I find the 1U panels the most practical, since you can combine several panels together and split them up according to your current needs. I sometimes use these panels for creating my own custom "rack tray" in the bottom of a rack cabinet: Mount one of these on the front rails and one on the back at the very bottom, then leave some space above in front and/or in the back to be able to access the tray. Good for storing cables, plugs, mics etc., and a lot cheaper than a factory made tray.