Adam Hall 61535B18 Rack Strip 18U blk

I used these strips in my studio to install rack equipment.
These things are heavy!(steel, as it says) Certainly strong, impossible to bend even even with a heavy load. In case you're wondering, I think there is no need to worry about the supporting frame too much.
Could be a little hard to cut if you don't happen to have the right tools.
I used the recommended Adam Hall 5653 nuts and those did fit great.

I got some of these to make up some multi-bay rack cabinets. They are good strong rack rails and having 3 mounting holes per U is a bonus, giving you more placement options and allowing you to save some space by using 0.5U ventilator panels etc.