Rack is 7'x4' with 6" sides. Frame was 2" angle at 3/16" thickness. Load bars to clamps are 1"x2" box steel 3/16" thickness. One piece of 2" flat bar that ran down the middle of the rack running the length of the vehicle. Floor is 3/4" 9 gauge expanded metal. Sides and top rail are 1/2" round bar. It is heavy and overkill but that's the way I like it. When I need storage room, I want to make sure I have it. Groucho's clamps are nice! I am sure they are some of the nicest available, if not the nicest. The ride is also more plush with the extra weight. Enjoy!